Diesel Guard warns drivers not to use regular fuel

Sometimes, a low-tech solution is all you need. If you're driving a diesel-powered car and don't want to trash the engine by accidentally filling it with regular gas, the Diesel Guard might just be the answer. The Diesel Guard is a $25 audio player that you mount inside your car's fuel-tank door. When you open the door, it lets off a loud beep and a stern warning to fill the engine with diesel fuel only. We assume someone's already making plans to hack these to say all sorts of less practical things when an unsuspecting gas-station attendant opens the door, but what we really want is one tailored for bio-diesel cars that says, "dude, this car only runs on fry grease!"

[Thanks, John]

[Martey @ Dec 19th 2005 1:38AM]

Alternatively, you could always attach a large sticker proclaiming "DIESEL FUEL ONLY." *That* would be "low-tech."

[Terry @ Dec 19th 2005 1:38AM]

Just like poster #1 stated.

"you could always attach a large sticker"

It was not that long ago where most cars had a warning printed on a sticker simular low tech to use only un-leaded gas, was it?

When did they stop selling unleaded gas?

[Foof @ Dec 19th 2005 1:38AM]

Don't regular gas pumps not fit/dispense into diesel stem fittings (and vice versa)?

[creamofcow @ Dec 19th 2005 1:38AM]

Foof, when I was a kid, I grabbed the wrong pump and started using diesel in a friend's car, the handle looked different but it fit.

[Ian @ Dec 19th 2005 1:38AM]

Yeah, technology has to increase for the increasing population of stupid people in this world. This is an example of that.

[Alpha4 @ Dec 19th 2005 1:38AM]

Gas-station attendants??!! Here in the UK we have to fill our own vehicles with fossil fuel.
And then pay heavily for the privelege.

[Michael @ Dec 19th 2005 1:38AM]

Alpha4, don't get your panties in a bunch; gas-station attendants are a dying breed in America--in fact, last I saw one in the states was about 7 years ago.

[SD @ Dec 19th 2005 1:38AM]

Diesel pump stems are thicker than regular gas stems for this exact purpose; to keep from using the wrong gas. This product seems pointless, or for the extremely retarded and very aggressive yes it will fit gasser.

[SD @ Dec 19th 2005 1:38AM]

...although unleaded would fit in diesel, but very wobbly and probably fall out. Still, if your that retarded you need your engine fried and not drive.

[Paul @ Dec 19th 2005 1:38AM]

Ha Ha !

I remember watching one of those american reality shows (amazing race ?) where the contestants were driving Diesel Mitsubushi double cabs (in Morroco ?).

On the way to the airport 2 or 3 teams filled up with Unleaded (the vehicles had a sticker stating diesel fuel only).

[Lauri @ Dec 19th 2005 1:38AM]

It was Amazing Race season 3 and the contestants were driving in Spain and heading to Morocco. And yes! There were big stickers stating "DIESEL" but no, they still chose unleaded.

[JB @ Dec 19th 2005 1:38AM]

So we're supposed to mount a small electrical device next to the gas vapour coming out of the furl tank neck?

Wise idea!

[Jane @ Dec 19th 2005 1:38AM]

Very sadly, yes, it is entirely possible and indeed easy to fill a diesel car with petrol. Despite the large friendly labels next to the the fuel tank telling you to use diesel. It's a very expensive mistake, which I will not be making twice. I hope. (No chance of forgetting, the way my colleagues keep sending me helpful links like this....) But I might buy one of those gadgets, just to be sure :)

[Duncan D'Nuts @ Dec 19th 2005 1:38AM]

"So we're supposed to mount a small electrical device next to the gas vapour coming out of the fuel tank neck?"

Bear in mind that diesel fuel isn't very volatile, so you'd probably be safe if you chose the correct nozzle in the first place. But the penalty for error if you already have the unleaded nozzle inserted might be quite onerous. Think of it as a self-induced Darwin selector...

[Brian @ Dec 19th 2005 1:38AM]

This is a bad idea. Only a total idiot could put diesel gas in an unleaded tank in the US... the hole's are different sizes.

Having said that, I knew an idiot that was faced with the different sized pumps. Rather than take a min to think about his mental capacity, he decided to use a funnel like device to pry the car's gas tank flap open so he could pour diesel into the tank.

So maybe it's not a bad idea..... :)

-brian.

[Eli @ Dec 19th 2005 1:38AM]

I guess that would make my wife a "total idiot". Depending on the age of the car (newer cars would probably freak out), however, putting a *little* bit of deisel in an unleaded car can be benficial (like say one gallon in ten). Filling the car's tank, however, will get you a bright-white-smoke-belching-lurch-mobile...if you can get it started at all.

[anthony @ Dec 19th 2005 1:38AM]

Way to go engadget! Thanks for mentioning biodiesel on your wildly popular blog!

[David Raistrick @ Dec 19th 2005 1:38AM]

A correction to the writers intended joke:

"...for bio-diesel cars that says, �dude, this car only runs on fry grease!�'

"fry grease" is not biodiesel. fry grease is WVO (waste vegetable oil).

WVO (and SVO, straight veggie oil) can be used to /produce/ biodiesel after refinement...but other things can also be used to produce biodiesel.

I'll hush now. :)

...david

[eeka @ Dec 19th 2005 1:38AM]

On the subject of gas station attendants, in NJ and Oregon (and possibly other states? anyone?) consumers are not allowed to pump their own gas.

Also, in all of the United States, a gas station with more than one employee on duty is required to pump gas free of charge for people with physical disabilities who have either a license saying they require hand controls or a handicapped parking placard or plate.

They need to make these for "premium fuel only" vehicles too!

In MA, where I live, there are plenty of full-service stations. You'd think that the attendants would know (especially where I go and the guy is also a mechanic) that a lot of turbo engines only run on high octane. But they don't. My 1.8 turbo VW requires high octane. I've had one attendant fill it with regular after I asked for high octane. Fortunately, they owned their mistake and siphoned the gas out. I also had a friend borrow my car and take it out a couple miles, then filled the tank. With regular. It was only half a tank, but it knocked and drove horribly. Fortunately I realized what was up and had my mechanic recommend an additive to fix that tank.

I then went and printed out a "premium fuel only" sticker.

I'd buy one of these if they made ones that screamed "premium fuel only."

[Ethan @ Dec 19th 2005 1:38AM]

Actually, diesel and gas pumps nozzles are the same size most of the time.

If you go to a trucker stop the diesel nozzles will be huge so that they can fill the large trucks faster (And diesel cars are designed to accommodate these). But at "regular" stations that have both, they are almost always the same.

[Kirk @ Dec 19th 2005 1:38AM]

Diesel misfuelling is a big problem in the UK which happens to a reported 300,000 motorists per year and a cost over over �80 million pounds in repair bills. A diesel nozzle is much larger than a petrol nozzle, so it much more likely that it will be petrol into diesel rather than diesel into petrol. Anyhow, if you have not had to foot the massive repair bill due to misfuelling then your bound to critisize the Dieselguard. Those who have misfuelled are quite happy to have peace of mind. Misfuel a modern Range Rover and you'll end up with a bill for �12,000.00!!!!

Dieselguard is available for the special LOW price of $9.95 to engadget readers with USA ZIP codes via [e-mail]

[reza @ Dec 19th 2005 1:38AM]

hi i h ve got a bmw 318i petrol engine
filloud out the empty tank with 20 liters of disele , after using more than 10 liters of this i noticed retrospectively that it was disele that i fillout out my tack with no petrol.
i didnt notice any problem with engine. i fillout out the whole tank now with petrol so now the ratio or disele to petro in my tank is 1:4 .
has it acuse any damage to negine ?
do i need to do anything?
Thanks

[robert @ Dec 19th 2005 1:38AM]

My wife put 7 gallons of diesel fuel into our car. The ran for about 30 seconds and then shut off. Is this correctable and how much might it cost to fix ?

[Turbo @ Dec 31st 2007 9:40AM]

is this still available in the us for $9.95?

[Don @ Nov 21st 2007 8:54AM]

Ethan, at "regular" gas stations you usually do find the smaller size diesel nozzle but I've found that Exxon seems to have the larger size nozzle at stations even in residential neighborhoods where there are few trucks. It's a pain in the neck trying to fill a diesel car with a truck nozzle since the nozzle will only go in a couple of inches.