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Fuel ISSUE!!! E85

J

J2000

New member
So I let someone drive my car resently and over herd me talking about E85 in my car... Well he didnt hear me say I need a few more things to run it. So he ended up putting 10 gallons in my tank........ Kinda at a stand still... Car seems to be running ok and im at 80% duty on the stock injectors.... Car does have a 255 Walbro in it so I know that the pump is fine... what about the rest????
 


First off...keep your foot out of it. Just top it off with 93 and run the tank low and refill with 93, nothing to panic about.
 
Would I just be Better off Buying the 65s and tuning it and calling it a day. Thats the last thing i can think of i need now for E85
 
Dont try to tune it on some random mix of fuel and everything else. You will want to punch a honda owner out of frustration. Just DO NOT go past half throttle unless you like chippy pistons. Put as much gas as you can into it and drive it nice. Your entire fuel system is going to get scrubbed spotless and your exhaust will smell delicious. You could possibly set a bank 1 lean code. If you aren't feeling too happy with that answer then pop a fuel line off and short out your fuel pump relay. Let it all pump out and refill with gas.
 


Just be happy your girlfriend didnt put diesel in it cuz she thought it would make it sound like a cummins she saw and when you told her it was a diesel she assumed she could just put diesel in the car and it would do that....
 
I ran it way down to E... Filled back up.. Car seems fine still. Now the big question is. I did order 65#.. Now when I switch to E85 should i drain the tank?????? I will be retuning for a better 93 octane tune then switching.
 
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DISCLAIMER: I dont know what im doing and no advice from me should ever be considered legally trustworthy

Also... do this in the summer. Summer blend e85 has more exploding corn in it. The reasoning is that when the blend switches in winter you will be slightly rich. This is good! Not only will your car start a bit better when it starts getting below -32c (0 in Freedom units) but it will also be a tad rich at wide open. This is also good because in the winter air is MUCH more dense and if you are already on the edge of too much boost chances are cold winter air will make sure you over boost. (On that crazy cold monday we had early january accross the country my car which normally makes around 14 psi of boost decided it wanted to make 18!!!!. I even maxed out my maf table at 11,500HZ that day if I went WOT) E85 Has a much wider "safe" range for fuel ratio so believe it or not 10:1 afr will make just as much power as 12:1. (Gas calibrated wideband)

My favorite way to do it requires you have a tuner handy. I typically do the usual injector swap and change the values in hptuners to match. Drive it a bit and make sure it is all peachy and happy. Maybe even drive it a few days. Next I make sure my maf chart is spot on near perfect on gas. Do a few data log runs and multiplys to get it locked in at zero or so that your long terms are ever so slightly negitive. Normal tuning stuff.

Now fun part. Run it as low as you can. Im talking to the point where you arent quite sure you will make it to the station. When you get there LEAVE IT RUNNING. Start filling it with e85 while scanning. You will see your short and long terms start to lose their ****. Thats ok you are trying to flush the gas out of the lines so it will start when you flash it for e85. (First time I converted I didnt do this and then the car wouldent start because it was still injecting gas... figured it out eventually) Let it idle for 5 mins. Grab a donut or a slushie. Pay for your exploding corn. Go back outside and shut it down. Multiply your injector table by .7 to start out with. Flash it. BEFORE YOU TRY TO START IT clear your fuel trims. Remember they were adding 30% or so and it wont be happy trying to start at +30%. Now start it up. Your trims will probably be off by a bit. Just drive around a bit. 10 or 20 miles. Let it settle in. watch for bad things like going lean on your wideband or kr. Did I mention be nice to it? Be nice to it for the moment.

Now its as simple as doing a data log of fuel trims vs maf for a 30 min drive or so. In theory it should all be -X% because back when you multiplied the injector table by .7 we actually added a little too much fuel most likely. Better safe then sorry. Now whatever percent your long terms are off just multiply the injector table by (1.05 if your 5% rich. .95 if your 5% lean) Get it back to zero or slightly rich (-X% long term) Now go have fun with your 2.59$ a gallon race fuel.

I have converted 5 or 6 cars to and from e85 using this method. Works good.
 
Leave injector table stock change stoich value in PCM to 10.7 Afr for e70 winter blend or 9.78-9.8 for straight e85. Check your wideband and roll out from there.
 


power enrichment afr comes to mind. If I set power enrich to 12 but stoic is set to 10 then wouldent the pcm be pulling fuel at wide open?
 


There are many MANY more flat out afr values in the pcm.... Including a hell of alot that we cant modify. Im guessing you have not converted a 3800 powered car to e85?
 
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