Car won't start after tuning back to 91 from E85 OFT
 

Hey all, I decided recently to change back to my 91 tune for the winter. After tuning the car starts by doesnt stay running. Any ideas on the issue? For reference, I went from STG2 UEL E85 tune to STG2 UEL 91 tune.

Any help would be great. Thanks!

Obvious question, did you run the tank to nearly empty and then fill with 91 before reflashing?

What was your procedure when you changed fuels and tunes? please be very detailed. Like when you filled, how much you filled, when you flashed, etc...

Running E85 on its tune the gas light came on. After the light came on I drove around another 20 miles or so to drain as much as possible.

Turned into the nearest gas station and pumped about 11.8 gallons of 91. Plugged in OFT to monitor fuel trims (didn't flash yet). After driving a mile or so, LTFT rose above 10 so I pulled off the street and flashed.

After flashing, the car ignites but doesn't stay up.

Sounds like you did it right. Sometimes the tablet just flashes bad or is buggy.

Try reflashing it again if that doesnt work then try reflashing the stock tune. You can also try to turn on the diagnostics before you start the engine and see how the trims etc are.

Check you flashed the correct tune.

if so apply a small amout of accelerator after start to keep it running car

a mile seems a bit short usually takes 3or 4 for petrol to get through system , its probably got a bit of e85 in ststem still ,

if all else fails flask back e85 tune run a couple more miles then flash petrol tune again.

you wont do any harm as long as you keep rpm low and light throttle.

Running 91 on an E85 tune should cause LTFT to go negative. You probably did not get the E85 out of your lines.

Check you flashed the correct tune.

if it was incomplete flash car wont start

if so apply a small amout of accelerator after start to keep it running car

Hello all,

Quick update, I flashed back to stock and it still barely started. After trying to ignite it about 10 times it finally started up. It took about 5 miles before LTFT started to fall, but it slowly fell and I think I should be okay for now. I should've been more patient with the process. Sorry for the panic post and thanks for all your replies!

+1

no problem, yes juist run the other fuel out a bit longer, as long as you go easy all will be good it usually takes 3 or so miles not just one

Why'd you switch back to 91 for the winter? Do the new crank values not work for starting up? :)