After reading this news story about diesel fuel mistakenly being sold as unleaded, I would like to know what happens to an engine that is given diesel fuel when it should receive unleaded.
The article mentions that the offending gas station will pay for any repairs that need to done to cars that filled up with the wrong fuel. What type of repairs will need to be made? Is this a major problem, or something that a simple flush of the engine can take care of?
The car dies, and the engine will not restart until all of the diesel fuel is gone.
If the technician knows about the problem it is a relatively simple (yet time consuming) fix.
Do the following
[li]Drain all the fuel[/li][li]Flush the fuel lines[/li][li]Replace the fuel filter[/li][li]Replace the spark plugs[/li][li]Put it all back together and restart[/li][/ul]
If the technician does not know that there is diesel (or is given an improper description on the work order) it might take him several hours to diagnose. Ask me how I know this.
Well, the other way around (unleaded in a diesel engine) wrecks the lubrication system. Even unlocking the car remotely can do damage as a diesel engine draws in a little fuel to warm before you start up the car. From the pages of the Telegraph, a UK paper.
Diesel in a petrol car would at least stop it from working full stop, diesel engines work at higher temperatures and pressures so I’m guessing the engine would at least refuse to turn over. I can’t find a link to any of this, its just my guess.
I imagine the petrol station would only pay up if fuel was fed to the wrong storage tank. Otherwise, nozzle handles are coloured and shaped so that you shouldn’t really mistake one for the other. I found this out when trying to fill my car with city diesel, they have yellow nozzle handles hence my slight confusion. If I had filled it up, it would have been my fault.
Here, diesel tends to be in a green-handled pump, and separate from the regular gasoline pumps. Also, the nozzle for diesel is about twice the diameter of one for mogas, so it’s impossible to even put it into a car’s tank by mistake.
A *little * diesel probably won’t kill a car or make it stop running - it’ll just run badly and be rather smoky. Ask my brother how he knows.
I’ve seen someone put diesel in a motorcycle before. The bike ran for about a mile or so and then started back firing. Quite impressive really as it was blue flame. I’m sure I wouldn’t want to deal with that mess, but at least it’s easeir then a car.
According to the article, the tanker delivering the fuel put diesel into the unleaded storage tank and unleaded into the diesel storage tank, hence the large number of people filling up their cars with the wrong type of fuel.
Another report I heard on a local radio station said that well over 1000 cars may have received the wrong fuel type. Seems like this could end up being a rather costly mistake.
OK, you asked.
Back in 1990 I was working at a dealer. I handed a work order for a 1973 P1800 Volvo that said “No Start”. Great. Least descriptive complaint ever. Did it die on the road? Did it not start one AM? Not really enough info to even start a good diagnosis. So I go to the service manager (who wrote the ticket) and more info. He said that the guy came out one AM and the car would not start.
I go out to the car and try and verify the complaint. Yup, it cranks, kinda starts and dies. Over and Over.
Now I never worked on this model car and this type of injection system when they were new. All I got is basic mechanical knowledge and my mark 1 brain with both cells firing.
So we push this shitbox into my stall. Everything I check is bad. I don’t this this car has been in a shop since Nixon was president.
Because of what I was told I am looking for something that has just degraded to the point that it no longer works.
Ignition points? Bad replace
Fuel injection triger points? Only one out of two sets working. Replace
Spark plugs OMG I have never seen such bad plugs. Replace.
Distributor cap, rotor and plug wires. Falling apart replace.
Car won’t start.
Check ignition timing. OK
Check cam timing OK
Check fuel pressure. Bang on spec
Do a fuel pump delivery test (Piss gas from pump into bottle) Fine Smell fuel for funkyness) nope smells like gas.
Check for spark Good spark (better have good spark all the pieces are new)
Check for injector spray. Good.
Check sensor inputs to computer. All within spec, or close enough it should run.
Talk to every old timer I can find including company technical specialist. They all respond that it beats the hell out of them.
At this point I have been working all @#^&*^&%%$# afternoon, and the car wants to start less then it did when I got it almost 5 hours ago. Did I mention that I am flat rate, and therefore, I probably made about $3./hour that afternoon?
So I decide to call it a day, go home and either get drunk, or see if I could get a job as a piano player in a whore house. As I am locking my tool box, I see the sun shining through the window, hitting the bottle of fuel. The fuel had a kinda of golden / straw color to it. That’s odd I thought, gasoline isn’t usually that color. So I pick up the bottle and smell. Yes it smells just like gas. So I spill a little on the table top (metal) and add a match. (Don’t try this at home, we are trained professionals)
The flames go flicker, flicker, out leaving a puddle of liquid. Guess what that smells like? Yup diesel.
I had taken the fuel sample from the cold start injector that was a line off of the main fuel rail and it dead ended at the cold start injector. When I pulled the line, it still had enough gas to mask the odor of the diesel.
The next day I drained the tank, replaced the filter, and flushed the lines. Wehn I cranked it up the car ran just like it had had a major service (Basically it had)
I went to the manager and told him to call and get me the real story.
Turns out the customer had bought gas at a full service station run by non-English speaking persons. The tank got filled the car ran for a few miles, and quit. Fuck, if I had had correct info to start with I would have been done in under an hour instead of six for which I got paid for maybe three.
The moral of the story is tell your nice mechanic if you think you might have mis-fueled. It will save time and money.
At about 4:1 gas:diesel it’ll still run, but pour black smoke out the back something fierce. Dad used to mix fuel like that for an ancient swather engine with sticky valves (since the diesel purportedly will act as a valvetrain lubricant). That motor was probably old enough to have been designed for leaded gas, and I think had been rained into with the headcovers (or maybe even heads…I think it was a Wisconsin flathead V-4, which wouldn’t have headcovers). I don’t recommend trying this with a modern car engine. For one, a diesel/gas mix will behave differently with a modern injector system compared to old carburated engines.
I’ve heard that in the old days, truckers used to deliberately add some leaded petrol to the diesel in their semis, for performance. I am unsure of the ratio used, but I believe there wasn’t much petrol. Apparently at night, you could see flames coming out of the exhaust when they accelerated hard.