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Tank full of E85 in a non flex fuel pickup

What can I do with a tank full of E85 in a non flex fuel 2002 GMC Sonoma? What problems will arise if I run the truck with the E85? How can I save my engine?

The biggest problem is that the ethanol will attack (dissolve) various pieces of the fuel system. The second biggest problem is that the engine will probably run roughly and get poor mileage. If you can’t empty out the tank and use the fuel elsewhere, can you at least use it up quickly, before it has time to do damage? When you get down to half a tank, top it off with straight gasoline (or E10 at worst). Repeat several times until you’ve got little ethanol left in the fuel system.

I would siphon it out and give it to a friend who has a flex fuel vehicle. Then I would fill the tank with straight gasoline. I would do this quickly before the E85 has a chance to damage any rubber or plactic parts of your fuel system.

If you’re old enough to remember when they made the switch from leaded to unleaded gasoline, you probably recall that they made the nozzle of the unleaded pump smaller and also the aperture for the tank so you couldn’t mix them up. I wonder why they haven’t adopted the same approach for flex fuel? If the E85 nozzle were made larger than the E10 standard of today, then this mistake wouldn’t be as easy to make.

If it were mine, I’d buy enough gas cans to hold 3/4 of the fuel in the tank and pump it out. Then dilute the remaining with E10. I’d gradually consume it by adding a small amount of the E85 into each fill up until it was used up.

i think your biggest worry is that ethanol burns alot hotter that plain will burn up your pistons,valves etc.everything else it does wont matter if your engine is blown…get it out of there a.s.a.p.

Probably nothing will go wrong with one tank, but to be cautious, siphon it out refill with fossil fuel.

Is it possible to get a siphon hose down the filler neck,maybe this is a tank removal situation.

The ONLY problem might be that the ECM can’t compensate enough so the truck will not run properly. You will be operating the engine in a very lean condition, the CEL should come on and engine damage (burned valves) could occur. Have you tried to operate the truck? How does it run? If it “acts funny”, surges and bogs down, don’t drive it until you remove the improper fuel…

A lean fuel air mixture burns hotter than a rich mixture. The only reason alcohol would burn hotter than gasoline is because the ECU can’t make the mixture rich enough for alcohol.
Alcohol burning racing engines actually run cooler than gasoline engines. Alcohol burning model airplane engines are difficult to make decent exhaust smoke with because the exhaust is too cool to properly vaporize the smoke oil injected into the exhaust.

I run varying amounts of E85 in a 99 Tahoe 5.7L V8 and 94 E150 5.0L V8 conversion van. My 94 E150 runs great on 2/3 E85 1/3 E10 and no CEL. The Tahoe runs good on 1/3 E85 and 2/3 E10. Your pickup may not start as easily, depending on how much regular gas was in the tank, because the ECU cannot increase E85 fuel enough, it takes more E85 to start than E10 or regular gas. E85 has not dissolved anything on my vehicles and does not run hotter, actually runs cooler. I strongly doubt you have any problem with E85 other than cold starts.

I’d think you could find a flex fuel friend happy to get FREE gas!

Siphon out half of it, fill with gasoline and drive on. When the tank is empty, add 3-4 gallons of the E-85 and fill it with gasoline. Repeat until it’s gone. Just buy 2- 5 gallon plastic gas cans and 7’ of 3/8" clear plastic tubing for your siphon hose. Have someone who knows what they are doing siphon out the fuel…