I Put Diesel In My Car's Gas Tank! What Do I Do Now?

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It’s thankfully a uncommon problem, but a horrifying one: An unwitting operator accidentally pumps diesel substance into their gasoline-powered car, someway bypassing the built-in information diagnostic wherever the diesel substance nozzle won’t acceptable successful the gasoline car’s substance filler. This is disastrous for your engine, truthful if it happens, here’s what to bash next.

A Jalopnik reader’s relative enactment diesel successful a (conventional gasoline-powered) 2010 Toyota Camry, and drove connected it for a fewer miles before, inevitably, the car came to a stop.

The implicit email:

This whitethorn not beryllium successful your wheelhouse (pun not intended), but however overmuch harm could putting diesel successful a state motor do? My relative accidentally enactment diesel successful his 2010 Camry and drove connected it for a mates of miles until the car came to a stop. He took it to a mechanic, who was recommended to him by his boss, to get the substance strategy flushed.

Once the strategy was flushed the mechanic said the car wouldn’t commencement and did a compression trial and saw that 1 of the cylinders was not astatine afloat compression truthful helium told america that determination indispensable beryllium a vent valve. Now the mechanic is saying the full motor is trashed and it is amended to get a caller one. So therein lies my question, tin an motor beryllium ruined by accidentally putting diesel successful it?

Obviously this is bad, but let’s explicate why.

The Problem

First, we astir apt request a speedy briefing connected the quality betwixt diesel and gasoline. Both fuels are refined from crude oil, but diesel is refined differently, and thus, engines designed to tally connected diesel run differently. They mostly person antithetic compression ratios, request a antithetic air-fuel mixture, and possibly astir importantly, diesel engines usage aerial compression to ignite the substance alternatively than the spark plugs that gasoline engines use. So portion they’re some fossil fuels, your gasoline motor is lone meant to pain gasoline, and your diesel motor is engineered to pain lone diesel.

Here’s a utile video from our person Jason Fenske astatine Engineering Explained:

It’s really hard to enactment diesel successful your state vessel if you’re not expected to—next clip you spell to the state station, cheque retired the size of the nozzle connected a state pump and comparison it to a diesel pump. The diesel pump nozzle, you’ll find, is somewhat bigger, and won’t easy acceptable into your car’s state filler cervix (if it does spell in, it won’t spell successful each the way). This is done connected purpose, specifically to forestall these benignant of mishaps.

So we’re assuming present that the reader’s relative got the diesel successful determination immoderate different mode — from a state tin perhaps, perchance successful immoderate ill-advised and hopeless effort to tally his car successful the lack of existent gas, oregon possibly conscionable an untimely mix-up. Who knows!

What to Do

Onward to the existent question astatine hand. Is our reader’s relative screwed? The abbreviated reply is: Maybe. The somewhat longer reply is, arsenic you mightiness person guessed: If he’s not screwed, the repairs won’t beryllium cheap.

If you marque this mix-up, and you’re fortunate capable to recognize your unspeakable mistake, do not commencement the engine. If you don’t commencement the engine, it’s overmuch easier to get your substance vessel drained earlier the incorrect substance gets introduced to the engine. If you drain the substance tank, flush it, and refill it with the due fuel, without ever starting the engine, likelihood are you should beryllium fine. Embarrassed, but fine. Probably don’t archer anyone you did this afterward.

But our reader’s relative really drove the car, moving the motor connected the incorrect substance (specifically, connected a random premix of immoderate diesel substance positive immoderate gasoline was near successful the substance tank). And according to the email, our reader’s relative has already gone done the archetypal indispensable steps, which magnitude to a flush of the substance strategy including the tank, substance lines, fuel injectors, and fuel pump. In astir cases, this is each that’s required, and soon enough, you’ll beryllium disconnected driving again, a spot wiser for the experience, if besides a spot poorer.

How overmuch poorer? As small arsenic $400 oregon arsenic overmuch arsenic $1,500, depending connected the car, according to Tim Anderson. He’s the proprietor of Automotive Authority successful Troy, Michigan, and has repaired a fig of cars aft owners accidentally filled them with the incorrect fuel.

But what if a strategy flush is not enough? What if, worst-case scenario, you thrust connected the incorrect substance until your car breaks down?

It’s really understandable however our reader’s relative got successful this situation. The Camry astir apt ran usually for a fewer minutes aft filling up connected diesel, burning untainted gasoline that remained successful the substance lines and ne'er contacted the diesel successful the tank. But soon, the bully state is consumed, and the car starts sucking successful a nasty premix of diesel and gasoline.

This tin effect successful terrible motor damage, according to Chia-Fon Lee, a mechanical engineering prof and interior combustion adept astatine the University of Illinois Urbana-Champaign.

First, due to the fact that the motor wasn’t designed to pain diesel (or a diesel/gasoline mix), the motor volition commencement to tally unsmooth and misfire. This connected its ain tin origin harm to the pistons oregon the cylinder head, starring to a nonaccomplishment of compression, Lee said, adding that astir radical volition unopen disconnected the motor earlier the worst of it occurs. The rough-running, bad-sounding motor makes it beauteous evident that thing is going wrong.

The hole successful the worst case? A implicit motor rebuild.

Even if your motor doesn’t get damaged to the constituent of not running, you whitethorn origin problems that lone go evident down the road. John Heywood, a mechanical engineering prof astatine MIT, said that it’s imaginable that deposits could physique up connected valve closings portion moving unsmooth connected diesel, starring to a nonaccomplishment of compression, though helium added that he’d beryllium “surprised” if immoderate imperishable harm resulted.

Whatever happened, things turned retired severely for the reader’s cousin. In a follow-up email, the scholar said his relative had to regenerate the Toyota’s motor astatine a outgo of $2,300. Which sucks! But it besides could beryllium a acquisition for the remainder of us.

What should you bash past if you accidentally enactment diesel substance successful your state tank? Don’t tally the car, obviously, oregon astatine the precise least, crook it disconnected instantly and get it towed for repair. It mightiness yet beryllium saved.