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About 4gallons of mixed gas in F150

My truck was on empty and someone put about 4 gallons of mixed gas in my F150. It will not crank. Please help. Should i use non ethanol to fill up?

If by saying that it won’t crank, you mean the starter won’t turn the engine over, that has nothing to do with whatever is in the gas tank.
However, if the starter will turn the engine but the engine won’t fire up, then it could be the gas.
I would think if it is a 50:1 mixture or s 40:1 the engine should start and run. I have even been able to start and run a four stroke lawnmower on a 16:1 mixture meant for a two stroke engine.

All of the gasoline that goes into my vehicles is mixed at the refinery, what is unique about your fuel?

This site has quite a few really knowledgeable mechanics but they can’t help with the little info you have posted.

  1. Mixed gas , just what does that mean ( fuel for a 2 cycle engine ? )
  2. Turn the key and nothing happens or the engine is being turned by the starter but will not actually run .

I’ve used probably 1/2 gallon of “mixed” gas in my car before with no issues. Of course, that’s with a full tank of “straight” gas.

I’d add some more “straight” gas to the tank and try starting it again. If it still doesn’t start, I’d rule out the gas being the issue.

I have also done that at the end of the season–with no resulting problems–in order to dispose of mixed gasoline/oil for a 2-cycle engine. However, we still don’t know if that is what the OP meant with the cryptic reference to “mixed gas”.

We’re still not even sure what he means by “crank”.
just adding fuel wouldn’t stop it from cranking/turning over.


No matter what fuel is in the tank, it will crank. It may not start, but the engine will turn over. You have a battery, alternator, starter or ignition problem. You may also have a fuel problem.


OP: “Cranking” is that rrr rrrr rrr sound you normally hear with the key in “start”. Your post implies you are no longer hearing that rrr rrr rrr sound after the four gallons of questionable gas was poured into the tank. Is that what you mean? If not, please clarify.

Ok. So it is 2 cycle for weed eater etc. It will turn over but sounds like its not getting gas.

It maybe the fuel pump but i dnt think its that. Its this gas issue i have

I don’t think it would make any difference using ethanol free gas. Filling it with either type of gas might help.
What you might try is spraying starting fluid into the air intake.

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What are the chances you dumped 4 gallons of diesel in, not mixed gas ?
If tank was as empty as you claim, it would explain your problem.

Who has 4 gallons of 2 cycle fuel on hand.
Brittmoe , you need a shop to fix this problem what ever it is.

People with outboard motorboats


I am assuming that the engine is turning over and not starting if that’s the case that someone must have put diesel fuel and your time diesel fuel takes more heat AKA Spark to burn fuel that’s why diesel engines have glow plugs that stay hot constant if that’s the case you need to drain the system completely and put fresh gas in keep trying to start until it fires I have ran 5 gallons a 40 to 1 mixture and a 350 Chevy didn’t have any problems is smoked a little but it fired right up you might want to check that

The OP posted that the mixed fuel was for 2 cycle engines .

OP posted that “Somebody Else” put in what they claimed to be mixed gas.

That is what the OP said 1 day ago . Until the OP says different I am going with 4 gallons of 2 cycle fuel .

If I had that problem I’d drain the tank, replace the fuel filter, and re-fill w/ a full tank of fresh gasoline. If that doesn’t solve it, the fuel pump may have been damaged, so a fuel pressure test would be the next step. I know many folks say it is ok to put 2 cycle gas, or even 4 cycle lawnmower gasoline that’s been sitting in the can over the winter into a modern vehicle to get rid of it. But I’d never do that myself. Too much risk. If a problem ensues, can be very expensive to correct.