Darrel Skubinna September 20, 2005 1:34 PM

I’m not sold that this is not a reasonable measure to take. The price of gas has put a crimp on a large number of families and I have heard that gas thefts were onthe rise. I was in a UHaul store the other day and the manager mentioned that UHaul drop off locations are fast becomeing favorite locations to score some free gas.

Andy September 20, 2005 1:38 PM

It looks like the shops want to sell these parts and feed the news to the gullible media:

Several police departments around Pittsburgh said they had not received reports of siphoning, though some police expect it may happen.

Zwack September 20, 2005 1:41 PM

It seems to me that a locking gas cap is a relatively cheap way of reducing the risk of having your gas siphoned.

The chance of having your gas siphoned is probably very low. The cost is also low, so this may indeed be worth it under a risk/benefits analysis. Of course quite a few older cars also have a drain on the underside of the fuel tank…

We have two vehicles, one has a door over the fuel tank that can only be opened from inside the vehicle (without damaging the vehicle, and if they’re that desperate they can have my gas…) the other one is kept in a garage and has both a tank drain and a non-locking fuel cap. It’s worth more than the fuel in the tank though, so again, they can take the fuel.

Yes, this seems over the top, but siphoning has been mentioned on the news here, and if it gives people peace of mind at a low cost then let them spend the money.


Michael Ash September 20, 2005 1:53 PM

The scare is unreasonable, but the idea of buying a locking gas cap seems reasonable to me.

A typical car’s gas tank at today’s prices might contain anywhere from $25 to $50 of gas, or more. If the car is parked on a public street then the gas is essentially unprotected except by the fact that it requires some equipment to remove, and the vehicle is presumably in plain view of the public.

If these gas caps are reasonably priced, then it seems like a decent idea to use one to protect that $50 of gas just sitting out in the street.

Not that it justifies any sort of scare. Gas was valuable before this month, too.

Mike Sherwood September 20, 2005 1:54 PM

Siphoning is a problem in some areas. Here (Arizona), there have been numerous reports of people drilling into the gas tanks to get around locking gas caps and anti-siphoning features in some cars. One of my coworkers had his truck stolen. It was recovered a week later with holes in the gas tank. Life imitates art – in this case, The Road Warrior.

Erik Carlseen September 20, 2005 2:00 PM


Having $50 worth of gas stolen is a little thing to someone like you who makes plenty of money. For others, it’s far more significant (I remember being there). It’s reasonable to assume this problem will be more prevailent in poorer areas with higher crime, where the impact will be more heavily felt. Can’t you show the same kind of compassion you do for people who are too poor to afford a voter ID card?

Erik Ableson September 20, 2005 2:13 PM

Well – it’s pretty much standard issue here in France on every car that I’ve driven. I suspect that it’s a market demand thing. Once the price of something becomes more than most people are willing to pay (perceived as being expensive). Given that gas is much more expensive here (still) it just makes sense.

The logical outcome is that they will become standard issue or at least the locking door… Especially if you subscribe to the theory that gas prices aren’t coming down any time soon.

Eli September 20, 2005 2:19 PM

They’re talking about removing the gas… that isn’t the only threat that locking access to the gas tank prevents. It also prevents vandals from putting sugar in the tank…which will cause you more costly problems than merely losing the gas.

And yes, I’ve worked on a ’65 Barracuda that had sugar put into the tank… it bent a lot of push rods before we got it fixed.

Davi Ottenheimer September 20, 2005 2:33 PM

Personally, I can’t understand why all vehicles do not have locking caps if they have locking doors. I agree with the comments above that the value of the gas and/or the value of protecting the gas from contamination outweigh the minor cost it adds to the vehicle. Perhaps I’ve just been exposed to more threats than most, but it makes perfect sense to me.

On the other hand I was recently told by a mechanic that there’s no need for locking wheel bolts on alloy wheels any more. I thought this was odd since the value of wheels has actually increased. His reasoning is that almost all the new cars have them already so black market demand is waning, expect in areas where people heavily modify older cars.

jayh September 20, 2005 2:33 PM

It’s more a matter of perceived fear.The change in price of gas is not enough to markedly change behavior, so a tank has another $10 worth of product than it did before. Product that’s awkward to get and leaves the thief out in the open. If rationing (real or defacto) occurs, than the dynamics could change.

There are a lot better and more rewarding things to steal and vandalism (the Barracuda) is not limited to gas tanks… cars are basically sitting targets to vandals regardless of a tank lock.

cbane September 20, 2005 2:37 PM

According to my brother (who works at an auto parts store), there’s not much point to getting a locking gas cap to prevent siphoning with any car newer than about 1986. Starting then, the manufacturers started putting anti-siphon screens on the tanks. It won’t prevent adding sugar to the tank, but fear of having someone put sugar in the tank isn’t what’s causing the run on locking caps.

Davi Ottenheimer September 20, 2005 2:47 PM

@ cbane

Good point. Interesting to add that some are claiming the locking gas cap was invented during the Great Depression…when compared to all the other security enhancements in a vehicle since the 1930s it’s probably worth noting that the dominant fuel type and the simple gas cap/flap/door have both changed very little.

Mike Sherwood September 20, 2005 2:56 PM


I don’t think the people stealing gas have done much thought on the incremental increase in the value of stored gas.

I suspect there is some psychological barrier that has been passed that makes people take stupid risks. For example, a 40 gallon tank on a truck, at $3/gallon could be worth over $100. People rob convenience stores for less than that. There are a lot of people who do not look at the cost/benefit ratio of their actions, and it appears a number of them are stealing gas.

People who don’t have much extra money are probably faced with a choice between stealing gas or not going to work and having to steal everything they need. In that situation, it’s easy to imagine how people rationalize their actions.

Anonymoss September 20, 2005 3:00 PM

As some posts have already mentioned, locking petrol caps have pretty much been standard over here in europe for a good number of years.

They deter only the opportunistic thief.

Anyone drilling holes into a petrol tank does not sound that intelligent! Especially when you consider that most (all?) petrol tanks come with a drain bolt (in a good number of cases this is easily removed – I had my petrol nicked in this way once, despite having a locking petrol cap!). After all, how do you expect a garage mechanic to safely do work (eg. welding, grinding, etc) near a petrol tank containing fuel?

James M September 20, 2005 3:01 PM

Just because the article indicates Pittsburg police are not seeing an increase in siphoning doesn’t mean it isn’t happening in other areas of the nation. Note this Dallas TV report where the local police are recommended purchasing a locking gas cap.

Or this article which relates a story of an entire cul-de-sac whose owners cars were targeted.

Adam September 20, 2005 3:22 PM

I bought locking caps for both my car and truck years ago when I bought them. It’s just a smart thing to do, and I did feel reassured during that current gas spike. Many newer cars only let you open the gas cap door from inside the car also.

Josh O September 20, 2005 3:41 PM

Here’s a better idea. Just never keep more than like 10 dollars in your car at a time. When kids kept breaking my Dad’s window to see if anything valuable was in his car, he started just leaving the doors unlocked. That way they can look and see without causing any damage. If they were gonna steal the car, the door being locked won’t stop them.

Anony Mouse September 20, 2005 3:43 PM

It’s been several years since I had a vehicle with a locking gas cap, because my current cars have doors over the gas cap that can only be opened (without damaging the car) from inside the car.

The last time I did buy a locking cap, though, it was in response to an actual and recurring problem where someone was siphoning gas from my car. The locking cap was effective in that instance.

Kevin Davidson September 20, 2005 3:51 PM

CostOfGas * ExpectedNumberOfThefts – CostOfLockingGasCap < Inconvenience.

Figure on average my tank will have 6 gallons and I doubt the siphoner will get it all. So 5.5 gallons * $2.659 (which is what unleaded was on the way to work this morning). That’s $14.62, about the cost of a locking gas cap.

That’s my security equation.

But those inside release levers are nothing. If someone is willing to siphon gas on a public street, they are surely willing to take a screwdriver to the flimsy gas filler cover.

USA Today reported that AutoZone, the nation’s largest auto parts chain, sold more than 10,000 locking gas caps last week, up more than 60 percent over a typical week. (DesMoines Register)

JD September 20, 2005 3:56 PM

Reminds me of the annual Christmas shopping season stampede to find the hot toy of the year for your kids, which of course is sold out almost everywhere.

Davi Ottenheimer September 20, 2005 3:57 PM

“That’s my security equation”

You’re leaving out the emotional distress from fear of a fuel tank bandit versus the piece of mind knowing that a bandit will move on to the next car that was made without a locking cap or that is not based on a fuel type less valuable/vulnerable.

BTW, are you indicating that a smaller tank size (subcompact car) is less at risk due to a smaller average amount of fuel?

Thom September 20, 2005 4:26 PM

Sorry. I think its only prudent. In the 70s my parents car was siphoned several times before my father bought one. I’ll learn from their lessons.

The investment is small enough. Just like porch lights and deadbolts. They may not deter anyone who’s determined, but someone just looking to score some gas will likely wander to the next car.

Nicholas Weaver September 20, 2005 4:45 PM

Also, a lot of american cars have gas cap doors that DON’T LOCK! Thus you have to have a locking gas cap if you want to seal the tank trivially.

This includes a lot of trucks with huge gas tanks: EG, I think the Hummer H2 has a non-locking gas tank unless you pay an extra $180 for the fancy chrome door.

With a 32 gallon gas tank, thats nearly $100 worth of gas.

Saar Drimer September 20, 2005 5:11 PM

I never understood why some manufacturers do not provide a locking mechanism for the tank (on the cap or from within the car.) Aside from stealing gas, vandals, or whoever wants to total your engine/car without burning it can fill it with anything but gas and walk away.

Can anyone predict the next item that will be a hit due to higher gas prices? Chistmass shopping has just begun.

CK September 20, 2005 5:57 PM

If you have a rational expectation that gasoline prices are going to go back down to $0.50 a gallon, then locking gas caps are a bit of overkill. If your rational expectation is that gasoline prices could go higher than they are today and stay higher, a locking gas cap is cheap insurance. No one would fault you for getting an insurance rider for your valuable art or coin or gun collection, why should anyone fault you for in effect getting a policy rider for your investment in mobility.

Baal September 20, 2005 6:17 PM

If people had any intelligence whatsoever (as a collective whole) they would unite peacefully against the use of gasoline and oil. It’s only when the gas prices go sky high people start looking for alternatives (most of which are not new science).

If you point out the Earth is being sucked dry of its bone marrow (oil) for our coffins on wheels, that the Earth is being sealed up like a tomb for these same coffins, they call you hippy or zealot or some other such nonsense.

Meanwhile, they’ll continue to howl about their gas prices while slithering out from their SUV’s with their fat rolls waving like a proud flag in the wind, as the Earth continues to try and throw us a clue with bad weather “KNOCK IT OFF HUMANS, YOU’RE HURTING ME” the Earth cries. It doesn’t matter, they rush to the store, one eye on their neighbor to see what the other has while buying something equal or to top it. Gotta keep up with the Joneses, you know.

Locked gas caps and closed minds, but hey what’s on survivor this week? O_o

ac September 20, 2005 6:56 PM

Gas cap locks just make your car less of a target than the next car. However, there are other things that make your car undesirable–in particular, having a small car. If your car is small and has a small gas tank, siphoning your tank has less of a payoff-per-siphon than siphoning the Hummer right next to it.

Furthermore, ginormous Hummer-sized trucks also serve as protection for the thief–it’s easier to hide behind a Hummer while siphoning than a Geo Metro.

Not to add fuel to the anti-SUV fire, but if you’ve got a small fuel-efficient car, you’re probably not the one who’s going to get siphoned. Not by a smart thief with a lot of choices, anyway.

Ranma September 20, 2005 7:01 PM

Well, My dad drives a Suburban, (Not every day, he has a much more efficient car for that), with it’s 40 gallon tank. Problem is the gas gauge is busted. So him and I take the burban out to get some wood from home depot and the engine quits about half a mile from his house. He can’t figure it out, calls the tow truck, the tow truck comes and we figure out we’re out of gas. Since the gas gauge is broken, my Dad fills up every time he takes the burban anywhere. I know this is ancedotal evidence, but he now has a locking gas cap on it. 😉

Davi Ottenheimer September 20, 2005 7:20 PM

@ Matthew Skala

Technically correct. Sugar is no big deal, but water and many other additives are a problem.

I thought the explanation on snopes was great. I especially liked their conclusion:

“the best way to gain revenge on someone through the ‘sugar in the gas tank’ prank might be to simply play on the belief rather than the reality — just sprinkle a fair amount of sugar on the ground beneath the opening to the fuel tank of your victim’s car and leave an empty sugar sack in a conspicious spot near the vehicle. Then sit back and watch your victim go wild trying to figure out how to deal with all that sugar he assumes is now in his gas tank.”

We’re all so gullible, I wonder if all of the locking gas caps are made by the same company and/or use the same key.

jammit September 20, 2005 8:07 PM

In my personal opinion, the locking gas cap is a decent idea to implement. It’s not over the top (hidden auto guns attached to a hidden switch in the gas flap), or too little (generic warning sticker saying siphoning gas causes hairy palms). It’s one of those ideas that won’t hurt to implement and doesn’t fail in a spectacular way (unless you loose the key).

Roger September 20, 2005 8:42 PM

It’s surprising to hear the so many American vehicles apparently require these. Here in Australia, as in Europe, either locking or internally controlled doors over the fuel cap have been standard on most models for so long that now it’s getting somewhat rare to see even an old bomb without one. (You do see some heavier vehicles without them — mainly diesel fuelled vehicles, which are presumably less attractive to thieves.)

That, by the way, gives a hint about the typical nature of this crime: most fuel thieves, and most victims of fuel theft, are relatively poor. Someone living from hand to mouth is less likely to have off-street parking, and more likely to have a very old car without built-in fuel security. But such a person is also going to suffer a lot more from having a tank siphoned, than merely the loss of $40, or $20 or whatever. If you don’t have an automobile association membership, and can’t afford to suddenly shell out for cab fare or a tow truck, suddenly finding your vehicle without fuel can be a remarkably severe inconvenience. (Yes, I am recalling my student days when I once trudged for miles in the rain to get a can of fuel — leaving my watch as surety on the can, the grasping bastard! — only to find my car had been vandalised in my absence.)

By the same token, it’s not necessarily true that the “change in price of gas is not enough to markedly change behavior”. If you are living hand to mouth, and you have budgeted $30 per week to commute to work, and suddenly realise that your $30 has already run out by Friday morning, you may face two choices: find $10 of fuel in a hurry, or lose your job.

Of course serious criminals also steal fuel, since it’s a largely untraceable, highly “liquid” resource, but they tend not to do the penny-ante siphoning stuff. Businesses with low margins and high fuel consumption (e.g. courier companies) are likely to be disproportionately affected by price rises, and anecdotal evidence from the seventies suggests that if the price continues to rise, desperate operators of such businesses may start to steal fuel, in a more organised way, tanker loads at a time; and then you will see other security measures re-introduced, like adding special dyes and markers to the fuel.

From the point of view of this blog, the interest in the story might be to decide if:
1. it’s a fiction invented by unscrupulous parts dealers (interesting possibility, but note that recently increased fuel siphoning has also been anecdotally reported in Australia!);
2. there is no increase in fuel siphoning, but people are reacting because they expect it to occur–whether out of panic, or through memory of the seventies fuel crisis; or
3. there has been an increase in fuel siphoning, but people don’t bother reporting it to the police because it’s pointless.

John Henry September 20, 2005 9:20 PM

I thought sugar in the gas made the engine run sweeter?

Seriously, is sugar soluable in gasoline? When I was in the navy, working in a ship’s engine room, we used to keep a small can of diesel fuel near the coffee pot. When our hands got filthy, a splash of diesel to dissolve the grime and a spoonful of sugar for some grit made a wonderful hand cleaner. Sugar does not dissolve in diesel.

Does it in gasoline?

John Henry

olivr September 20, 2005 9:42 PM

Actually, Bruce…

This is NOT unreasonable. I would have agreed with you about a week ago, though.

Apparently a significant number of people in my neighborhood have had gasoline stolen from their tanks in the last week or two. This is in the New York Metropolitan area, so there’s a significant crime rate, anyway. Where criminals were before stealing loose items on the seats, they’re now popping the gas cap.

As EVERY car has gas in it, and not all cars have something worth stealing on the seats, this makes it much harder to defend yourself. So in this regard, the tank lock would be a good thing. Probably not any better than putting a flashing LED in your windshield, though.

Perhaps, more to your point, all those people in the suburbs running out to their local box store to buy this unnecessary piece of protection is ridiculous. Here, though, the threat is not minimal.

At any rate, we have a very reliable public transportation system in this area. Really, the advantages to owning a car here usually are drastically undermined by the increasing costs to a) fuel and b) secure one’s car. Also, as an environmentalist, I’d hope that these increasing costs will drive many to utilize the public transportation system.

Bill McGonigle September 20, 2005 10:10 PM

Bah. I’ve taken the opposite approach, installing a spring-loaded gas cap in my car:

(first hit in google – no idea about the vendor)

The way I weigh this is that I’m far more likely to drip fuel on the dangling gas cap, then onto my hand, then onto a $75 pair of slacks (ruining the slacks or showing up at a client stinking of gas) than I am to have someone siphon all the gas out of my car. To cover that small potentiality I have AAA.

So, do your attack trees and cover the edge cases with insurance. Thank you Sensei Bruce.

Davi Ottenheimer September 21, 2005 12:20 AM

@ John Henry

Correct. Sugar doesn’t dissolve in the fuel, but it does dissolve into water that condenses in the tank. So instead of water just evaporating on being heated it coagulates and gets jammed into the filters/pumps…not exactly good for the engine.

It seems to me that the clever way to sabotage a gasoline engine is probably to actually add water (with or without sugar), diesel or kerosene.

Rampo September 21, 2005 3:29 AM


Last time I fuelled a car in the US, near San Franscisco, I had to pay the filling station cashier before I could get any petrol out of the pump, something I’ve never seen in Europe, where one pays after fuelling — even on motorways, where one could easily escape.

Suddenly there’s big excitement in the US about locking fuel caps. I don’t think one can buy a car in Europe which doesn’t have a locking fuel cap. You mean the Usonians don’ have them?

The two positions (prepay filling station but no caplocks versus postpay filling stations yet caplocks) appear illogical.

Rampo September 21, 2005 3:38 AM

Come to think of it, theres another good reason for having a key-locked petrol cap — if joyriders steal the car by hotwiring it, they can’t easily refuel the vehicle, limiting their range.

Mike September 21, 2005 3:49 AM


Ever been to Liverpool? The only place I’ve been to in Europe where you have to pay first, and you’re not allowed into the actual shop which is locked up and protected by cages.

In one of the rough areas the local booze shop is a caged corridor to the counter, with all the products behind.

One myth that is true is about scoucers.

Neil Bartlett September 21, 2005 5:09 AM

I didn’t realise that locking petrol tank caps weren’t standard in the US. Perhaps I should buy a few and sell them on eBay…

Gareth September 21, 2005 5:38 AM


Driving off doesn’t work in the UK because the stations CCTV has your number plate on record – you will be caught and chastised.

In the US, OTOH, I believe there are still circumstances where you can drive without plates – the last hire car I drove over there had no plates because it was brand new. It struck me as odd at the time, but it means CCTV isn’t a complete protection against drive offs. Hence the differing security choices.

pfh September 21, 2005 5:43 AM


You do lead a very sheltered life. Try Stoke-on-Trent or Wythenshawe and, I’m certain, a host of other depressed areas. It’s not a Scouser thing, it’s a deprived area thing.

And the thing I hate about the US gas stations is that what the pump says (pay first, pay later, pay at pump, …) and what actually happens appear to be completely unrelated. If you try to do what the signs say – you get looked at like an alien.

dave September 21, 2005 5:50 AM

The other advatage of having a locking petrol cap, is that you cannot remove your key from it when it isn’t in the car. This means that it is impossible to drive off and forget to put the petrol cap back on. In the long term, everyone’s a winner

Mike September 21, 2005 6:23 AM


I know exactly what you mean, I live a bit too close to Stoke – recently voted Briatin’s worst city – and will soon be moving to Hulme near Moss Side. Where I won’t have to lock my feul cap as it will be kept in a secure parking compound in the centre of the housing block.

Christian Kaiser September 21, 2005 6:59 AM

Interesting. Here in Germany, nearly all cars have locks on the caps. I would never have come to the idea that in the US, they are rare… funny.


JD September 21, 2005 8:40 AM

Before you buy a locking gas cap, try getting a siphon hose into your own tank. I thought gas tank anti-siphon features were commonplace (?) — anyone know data on that?

Zwack September 21, 2005 10:20 AM

Anonymoss said “Anyone drilling holes into a petrol tank does not sound that intelligent! Especially when you consider that most (all?) petrol tanks come with a drain bolt (in a good number of cases this is easily removed – I had my petrol nicked in this way once, despite having a locking petrol cap!). After all, how do you expect a garage mechanic to safely do work (eg. welding, grinding, etc) near a petrol tank containing fuel?”

Not all fuel tanks come with drain bolts. One of our cars (a 1964 1/2 Mustang) has a drain bolt in the gas tank, but the other (1995 Jeep) doesn’t.

As I’ve had to replace the gas tank on the Mustang before (pin hole leak) I know that the drain plug can rust in place (which is a pain to deal with) and the replacements are available both with and without a drain plug.

Drilling a hole in a gas tank to get the gas is fairly safe as long as you don’t make any sparks when withdrawing the drill from the tank, but seems pointless as Gas tanks have several openings all of which can be used to remove gas from the tank easily.

On all of the vehicles I have worked on the gas tank has a filler cap/hose, a hole for the fuel sensor to go in (usually the biggest hole on the tank) and a hose running to the engine compartment (with a filter on it usually). Some of them have drain bolts too, but they’re less common. If I was told to take the gas out of a vehicle, I would crawl underneath, find the fuel hose, disconnect it at the fuel filter or cut it somewhere and pump the gas out from there. Little risk and easy to do. With a fuel pump ($33 new from an auto parts store, you can probably get them cheaper without any problems) you could speed up the process significantly.

I would expect a competenet mechanic not to do work like welding or grinding close to a gas tank containing fuel unless he has taken the usual precaution of filling the tank with inert gas. One simple (backyard mechanic) solution is to connect a hose to the exhaust and put it into the tank and then run the engine for a while. Even if the mechanic has drained the tank I would expect him to flush it before working because otherwise he is working with a container of an air fuel mixture that is just ripe for an uncontrolled chain reaction.


CF September 21, 2005 10:25 AM

I had a friend of a friend in high school that never paid for gas – he siphoned it all. He used a small metal pry bar to pop open the locked door (it is only held by a small latch), which he said added 2 seconds to the theft. He also used a siphon hose with a hand pump built in. In parking lots he would siphon directly from the victim’s car into his.

Davi Ottenheimer September 21, 2005 11:06 AM


The sugar needs water in the tank to dissolve. Condensation in the fuel is usually not a huge deal, depending on the fuel content and design of the engine, but if you do get enough water/sugar in the tank the filters and pumps will become clogged and starve the engine for fuel. It’s a myth that sugar dissolves into fuel and gums up things, but it’s true that putting water into the fuel kills the engine, and water with sugar is obviously a worse mixture than water alone.

Anyway, I wouldn’t worry about it too much as the threat from evil chemists is pretty low. I just find it interesting that the actual fuel and fuel-door designs have changed so little over the history of cars, especially compared to all the other advances in technology.

Rampo September 21, 2005 11:08 AM


“Driving off doesn’t work in the UK because the stations CCTV has your number plate on record – you will be caught and chastised.”

Why on Earth would one use one’s own plates on one’s car? Get fakes online, no questions asked:


“You do lead a very sheltered life. Try Stoke-on-Trent or Wythenshawe and, I’m certain, a host of other depressed areas. It’s not a Scouser thing, it’s a deprived area thing.”

Yeah, you’re right: my business rarely takes me to places where there’s so little money.

Davi Ottenheimer September 21, 2005 11:14 AM

@ Rampo

Good thought, but manual replacement of plates is nothing compared to 007’s method in the Cannonball Run. His car had a system similar to the rotating billboards — press a button and the plate rolled to another number.

cdmiller September 21, 2005 2:35 PM

Absolutely nothing wrong with locking gas caps. I leave one on a 4 wheel drive that spens lots of time parked in a remote location. I have had friends return from a camping trip to discover someone placed dirt and twigs in their gas tank while it was in the trail head parking lot, they had a fun trip home. I have not known anyone who found their gas stolen. If gas is now regularly being stolen perhaps this points to a larger problem of the growing division between the haves and have nots.

Rich September 21, 2005 3:19 PM

“People in this country freak out at the slightest little thing”

Not sure what Bruce meant, but I think the ‘freak out’ part is that it’s in the news. So you can’t buy a locking gas cap this week. Wait until next week. You’ve gone without one this long, you can probably wait another week. Worst case, don’t fill up more than a 1/4 tank.

People are acting like nobody is ever going to make locking gas caps again, and if you don’t get one NOW you’ll forever be without.

Lyger September 21, 2005 4:10 PM

I’d think that there are two considerations here, which are different from each other. As umpteen people have pointed out, buying a locking gas cap is a reasonable precaution to take against people siphoning gasoline. A run on auto-parts stores to get the lockable gas caps might, however, be perceived as the beginning of hysteria surrounding gasoline thefts. We in the United States do have a tendancy to overreact to publicized threats without really knowing how much of a threat there really is. There are a number of ways to steal fuel, and there are a number of ways to protect oneself, and there are a number of ways to reduce the demand for fuel so that theft is not so much a problem. But the common pattern here is for a problem to arise, someone to find/promote some solution to that problem, and then everyone and their grandmother to jump on that single solution to the problem – to the exclusion of everything else. Now, maybe I’m giving Bruce too much credit, and he’s busily snickering behind his beard at all the poor saps running out to buy locking gas caps in an attempt to deflect the threat onto someone else. But I’m thinking that it is, perhaps, the lemming-like rush to this single solution that has him scratching his head in wonder.

JOJO September 21, 2005 11:17 PM


I live in South Mississippi right where hurricane Katrina hit. probably every car that was there for the h-cane in the neighborhood was flooded. of course the gas lines after the storm were too long to consider waiting in . people were spending the nights in the lines.

everybody in the neighborhood was trying to siphon gas out of there flooded cars to put in functional cars so they didn;t have to wait in those lines. The only car that we have heard can be siphoned out of the gas tank was in my grandpas 83 mercedes that was at our house.

So everey one else had to like jack there car up and disconnect some stuff from from the tank from under the car. very time consuming.

I guess if you didn;t care about damaging the tank you could drill holes easier.

im pretty sure anti siphoning valves have been standard for at least a decade probably more. every car in our neighborhood had one. and everyone we talked to.

A locking gas cap is pointless, althought it will probably make some money from some idiots.

another_bruce September 22, 2005 1:30 AM

city versus country thang. my last truck came with a locking gas cap, i lived in the northern san francisco bay area then. down there in some places if you leave it parked too long after dark they’ll take the stereo, the wheels and the gas. here in oregon, no problem, my current truck has ordinary gas cap, unthinkable that somebody would siphon, the big gas issue here is that self-service is illegal. you city folk have to worry about your gas, but you have a lot more to worry about than that.

Sascha Welter September 22, 2005 2:27 AM

Some anonymous wrote:

After all, how do you expect a garage mechanic to safely do work
(eg. welding, grinding, etc) near a petrol tank containing fuel?

Haha! Don’t you know the old story of the bike mechanic who had to weld on a petrol tank? He emptied it, looked inside, then shook it to make sure everything was dry, no drops sounding. Then he started welding and big BAAAANG! Gasoline/air mix is what is explosive, not just gasoline.

When welding near a petrol tank your best options are to have it filled up or removed completely.

My grandfather was a mechanic and he used to have an open bucket full of gas standing around in his shop. It was where they put out their cigarettes.

As for the locking caps: I believe the perceived risk is not only losing a bit of money. With the hurricane in the USA, people are probably afraid of the chance to loose the gas in the advent of a desaster, limiting your chance of survival. Double scary and even less likely.

alex September 22, 2005 12:50 PM

There’s nothing people can do about gas prices going up.

There’s nothing they can do about the length of their commute.

There’s nothing they can do about the 14 mpg SUV they still owe $30k on.

If I’d painted myself into a corner like that, I might buy a $15 locking gas cap too, even if all it did was make me feel better.

gas2high September 23, 2005 8:23 PM

I feel that buying a locking gas cap might be a good thing. I am trying to find one for my vehicle right now and came upon this website and read a few of the posts. I didnt exactly agree with the person that feels that its not a big deal. Well, I feel that it is. I dont make alot of money like some people and to me the 50.00 worth of gas that is in my tank is worth alot, since I have to have that to get to work and back each week! It is not right for a theif to steal from you, when you dont have much either. My dad just got done having open heart surgery for the second time, and while he was in the hospital, someone siphoned a whole tank of gas out of his truck. Now that is pretty bad. These people should be ashamed of themselves!!
Fed UP!!

THERICHJUSTGET RICHER September 27, 2005 7:32 PM

I dont know about some of you, but Im really tired of hearing about the SUVs that everyone supposedly buys. Many people prefer SUVs because the are 4×4 and are much better on bad roads then cars and trucks are. I have had many front wheel drive cars, and have had bad luck with them on the snow. I have a SMALL suv that gets about 20 MPG, which is not great, but not bad either. I also have a SMALL car that gets 31 MPG that I drive back and forth to work. I am just tired of people putting people that have SUVs in a different category, as if they deserve that the price of gas is high because they own an SUV. Lets get real!! I also dont owe 30K on it, I didnt even pay 1/2 that much for it!! Some people dont have that kind of money!

melinda September 29, 2005 3:03 PM

I own a 99 Pontiac Firebird with a V-6 If someone put sugar in my gas tank, what will happen and is there anyway for me to find out if this has been done.Thanks

Tethered Rose September 29, 2005 5:20 PM

@ melinda

“I own a 99 Pontiac Firebird with a V-6 If someone put sugar in my gas tank, what will happen and is there anyway for me to find out if this has been done.”

It will lock up your transmission immediately. I’ll have to check with my resident expert to see how to find out if it’s been done before you start your car.

No matter why someone would want to do that, it’s a Bad Idea.

I could go around and put sugar very stealthy-like(!) in about oh, say… maybe 1,000 cars at once. If I wanted to.

Boy would that/those companies be pissed when no one showed up for work. Especially our Police Task Force in various cities and country sides.

Dumb. Really Dumb.

Tethered Rose September 29, 2005 5:23 PM

“I’m not sold that this is not a reasonable measure to take. The price of gas has put a crimp on a large number of families and I have heard that gas thefts were onthe rise. I was in a UHaul store the other day and the manager mentioned that UHaul drop off locations are fast becomeing favorite locations to score some free gas.”

That’s okay. Hurricane Katrina recovered a lot of Government Funds! What a good thing to spend some Money on!

Davi Ottenheimer September 29, 2005 5:28 PM

@ melinda

See my comments above…sugar doesn’t dissolve in gasoline, but water in your tank can absorb the sugar and make it clog your filters causing some minor issues.

Tethered Rose September 30, 2005 10:51 AM

@ melinda

It will not lock your transmission. It will lock your ENGINE, immediately.

There is no way to tell if it has been done other than to look for residue. Locking gas caps are a Good Idea, as a Deterrent, as long as the locking gas cap is Vented.

The lockable gas doors (openable from the inside of the car) are another Good Idea, as a Deterrent.

My apologies for my quick response.

Bee safe.

Tethered Rose September 30, 2005 11:06 AM

@ dave/melinda


IF condensation/water builds up in your tank;
it goes to the Bottom of the Tank.

IF sugar gets in the Tank;
it goes to the Bottom of the Tank.

IF you run your car until your gas Tank gets low on Fuel;
there will be enough Sugar in the Gasoline (over time) (that it leans the engine out);
it will Damage:
the Valve Guides,
it will Cause:
the Residue,
after Ignition:
the Cylinders will stick to the Cylinder Walls (after Combustion)
and Cause Damage;
to the Piston Rings,
AND the Cylinder Walls,
AND the Valve Guide,
AND the Valves.

It happens over a Period of Time.

We can show you 5 Engines that it has happened to.

Any doubt;
Call any:
Manufacture of ANY Engine,
OR Machine Shops that REPAIR Engines,
OR Car Dealerships
AND they will VERIFY.

(*5 pounds of Sugar is the Lethal Dose!)

This is a Recipe for Disaster. If in the wrong hands, could do BAD THINGS.
Please Get The Word Out.


linda October 14, 2005 3:38 PM

please can someone answer this question? i was driving a 2005 toyata corolla, i was sure i got gas siphoned out of my tank when visiiting a friend, …i thought my friends dauther and boyfrind siphoned my gas out….then my friend told me it couldnt have been them as the 2005 automobiles are siphon proof and cant be this true? or is there a way to do it with special siphon equiptment? im so sure i was siphoned!
what is the explaination? thanks. linda

Anthony October 16, 2005 3:52 PM

I am getting concerned about my company’s semi trucks and trailers. Diesel is arount $3/gallon out here. Diesel also works in home heating oil systems. A semi holds several hundred dollars worth of fuel. I just hope the meth-heads never figure this one out. Diesel fuel theft is a problem for farmers who make the mistake of leaving equipment out in the fields.

Davi Ottenheimer October 16, 2005 5:21 PM


Ah, yes, it’s not exactly clear why diesel has jumped higher than other fuel prices, but one thing is for sure: Diesel’s original intention was to create an engine that did not require dependence on foreign petroleum sources, or the corporations that controlled them.

Many people point to several key economic reasons for the rise in prices this season:

1) As you point out, diesel prices are impacted by the demand for heating fuels (distillates) so it has a seasonal fluctuation.

2) About 95% of production in the Gulf region is still not back on the market. This is probably related to the fact that over half of the Gulf platforms and a good number of drilling rigs aren’t running yet, not to mention 10 or so refineries are closed in LA and TX. Altogether this is apparently an impact of about 10% of total US production.

3) Speculators aren’t stupid and they find ways to increase demand in order to contribute to the rise in prices and get better returns on their investment.

That’s all fine and dandy on some level, but it reminds me of the letter from Shuster to the Energy Secretary back in 2000 when prices were doing something similar:

“We have received numerous reports regarding the alarming spike in diesel fuel prices, the most dramatic of which has New England customers paying 40 cents more per gallon than they paid just one week ago. By any account, diesel fuel prices appear to be rising out of control.”

No Hurricane to blame back then. Quite the opposite, a Congressman wrote the US Attorney General because “we believe to be price gouging and manipulating of consumers”.

Again, that corresponds to Diesel’s own description and prediction of petroleum-based engery corporation behavior back in the 1800s — the very reason his engines will run on oil or fats from just about any source including fish, meat, vegetables, etc..

Moreover, as we know today, the market was in fact being manipulated in 2000 and consumers were being, please pardon my french, screwed by Enron:

“U.S. Rep. Jay Inslee announced this evening that he will offer an amendment next week to energy legislation in the U.S. House of Representatives that will help provide refunds to consumers and the Snohomish County Public Utility District (PUD) for high rates resulting from energy market manipulation”.

One last thing to consider is that the US military relies heavily on petroleum diesel production and has done a great deal to enhance/modify diesel engines for everything from ships to motorcycles (not to mention advances in trend analysis and condition based maintenance), but for some odd reason they haven’t done much to change the source of the fuel to something domestically and more sustainably produced (like B20 or even B5, which is working quite well in Europe).

khk November 1, 2005 4:30 PM

I just bought a 2005 chev cobalt, I can’t find a locking gas cap. I talked to Chev at 1-800-222-1020 option # 4 and was told I they would close my file as not satisfied, and I they would send me a form to contact the better buisness. I told them that I paying for a $15,000. vehicle that I cannot protect, due to a $10-15 gas cap. I asked they who would be responsible for paying for my car if my can was vandalized. Their response was the insurance company. I asked him why should my insurance company pay for Chev. failure to protect its consumers.

Pissed Off December 17, 2005 4:38 PM

We freak out at the slightest little thing? I dont call getting something stolen a little thing. Watch what you say before you say it next time.

jimmy June 10, 2006 7:14 AM

Someone (my illegal eviction landlord try to sell the house) put the white sugar mixed with water in my gas tank last night. Until I find out about this, I already drove down on the road about 8 miles. I file a police report. I report to my insurance and waiting for the adjuster come to check it out in TOYOTA repair shop. How much damage might be happened to this 2005 new 7 people van? Do you think the explosion will be happened if I do not know about it and continue to dirve with all my families inside the van in the freeway(landlord can evict me out of the house without relocation fee)? How to protect my gas tank in the future? Any other suggestion?

janet July 13, 2006 10:35 AM

how can i correct the damage of gas and sugar mixture, abt 6 ozs, before the car is started

Dave December 21, 2006 5:02 PM

I live in Philly. Someone broke off my locking gas cap and left me almost empty. My truck holds 20 gallons.

David March 1, 2007 10:04 AM

FACT. IT HAPPENED REPEATEDLY TO ME. ESCALADED TO 4 THEFTS IN MY HOME, incl. my Identity, 2 $5,000 LAPTOPS, 1 Desktop computer, 3 expensive cameras, iPOD, Credit Cards, Passport, and much more…

So add to typical & historic (perhaps hysteric) reasons / debate:
High Gas Prices
+ Increasing Econ Hardships(low/mid level)
+ Increasing Drug Abuse (esp. Meth)
+ Increasing Homeless Drug Users living/travelling in their CARS
+ High Availabilty of easy targets
+ Overcrowded Jails -no arrests for petty crime even disinterest of police


EXCEEDINGLY MORE than most of us value our homes, our families, our jobs, & our futures


Bob G. June 7, 2007 11:09 AM

If I have the money to afford a Ford Excursion V10 (12.4mpg) don’t I have the right to own it. I did work hard for my paycheck why should the government or anyone else tell me how to spend it. This may sound ignorant to anyone but give me hard proof that my driving around town is having a direct affect on the the world climate. You can’t, I choose to drive what I want. Just like you choose to fight the fights you want. It all comes down to a matter of what you can afford and not.

publikwerker July 15, 2007 4:31 PM

Here in Portland, Or, I’ve had my gas stolen
twice in a month, so now I’m buying (online)
a locking gas cap.
and to the poster above this post,
yes, it does sound ignorant to say
that there’s no proof that driving your Excursion
doesn’t directly affect the world climate.

Bill August 7, 2007 11:10 PM

I just bought a dodge dakota and am going to buy one of these gas caps, not because of someone stealing the gas. but for fear of someone putting bleach or pepsi or sugar in the tank. My house has been egged and had someone drive through the grass two days in a row. I am getting one not for theives, but for vandals.

prevention October 23, 2007 10:45 AM

what are 100% effective vehicles/measures/countermeasures/ways/methods for preventing gas cap and/or fuel tank tampering and/or spiking?? i have not read one all inclusive solution to someperson siphoning my tank or spiking it with a water?orsugar tactic.this fool has done it to more than me AND the police know about it,but says without a witness or signed confession,theres nothing they can do[or want to do] so short of killing this mook,I WOULD APPRECIATE SOME SOUND PRACTICAL SERIOUS FEEDBACK.please thank you
p.s. i am not really going to kill him.onlyin my mind.he has and will stepped on so many toes that someone else will do him. back to my inquiry?any?suggestions to keep him out of my gas tank?

hugenot March 2, 2008 7:58 AM

Sorry dudes,

“you’all??? wrong – SUGAR will dissolve in ethanol which is ever-present in today’s gasoline in greater and greater quantities

Clive Robinson March 2, 2008 4:31 PM


Can you still wash it out?

Many years ago when I was wearing the green I was shown a very practical soloution to sugar in gas, simply pour into a large container add the same quantity of water and agitate. Then siphon of the gas as the sugar tended to stay in the water.

What hapens with the ethonal which I belive is happy to be in water as it where….

ThisisNewYork May 29, 2008 3:07 PM

Well lets see…gas is now $4.15 a gallon. MAYBE its reasonable to get a locking gas cap after all. This forum was created in September 2005 (good ol’ days of gas prices compared to now). Analysts are now suggesting that THESE are the good ol’ days of gas since gas is expected to be $7 A GALLON by summer 2009!!! Need I say more…Protect your gas people!

withoutaride June 24, 2008 5:41 PM

My husband fitted my car with a new locked gas cap a few weeks ago. I needed gas today and when I put the key in the cap, the barrel mechanism fell out and I am unable to remove the cap to fuel my car. (hubby is on fishing trip) any ideas on removing the cap? I have my old one if I can only remove the broken cap.

Greg June 27, 2008 12:56 PM

Having a locking cap may stop the occasional petty thief but if someone wants your gas bad enough they’ll use a pry bar & not only get the gas but damage the filler tube and the fender too.Is it worth it? By the way, whether you’re stealing gas “to get to work” or to sell, a thief is still a thief !

cargantua September 8, 2009 4:39 AM

there is a new scam in town, people steal a small amount of fuel from many cars, making the owners mostly unaware that any fuel is missing, there are many easier ways to take the fuel out other than through the filler cap. the tank also has a vent hole – ever tried to fill a bottle? the air needs to come out first! – any mechanic will know all the tricks!

EMS February 11, 2012 7:52 AM

All this talk about whether anyone will really steal your gas is mute.

How about some practical advise on which manufacturers put out the best locking gas cap models ?!
I can only find those cheap plastic ones. I bought one years ago for a previous car and it was easy to remove – without the key. The gas station attendants would remove them all the time, without the key!!!

So, if anyone can Name a GOOD one… please post it here….

Thank you.

Dennis March 6, 2012 7:01 AM

Also, lets not forget the old “Say Smokey” column that Pop science used to put out – he was trying to figure out one day why water was in the gas of a car – traveled to the person’s home – checking things out – when he saw the neighbors kid take a garden hose, stick it in a cars tank, and turn on the water. He was playing filling station!

TFoster October 9, 2012 12:06 PM

Gas caps not a real stopper. My husband put one on his and we have since had an entire tank siphoned off. Since we had just filled up we thought the car had an electrical short somewhere (Montana’s are natorious for them) and have been throwing parts at it trying to get it running. Only to find that the tank is empty. It stopped running while we were driving because it was OUT OF GAS! The idiot didn’t just steal from us he put our entire family on the side of the road! So we will be finding some other way to prevent the siphoning and hopefully, if we can get a car to replace my van real soon, I plan on investing a few dollars to put some gas in the tank one final time. Along with some water, sugar and maybe a little sand. 😉 Then all I have to do is “listen” for someone having “problems”.

alex September 22, 2016 3:25 PM

I know this may sound silly but several times I have left my gas cap on the roof of my jeep wrangler. any way I can secure it so il don’t loose it.

Rose Herbert June 28, 2019 7:05 AM

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