Well my cars been converted to e-85 for about 2 months now. I have fic 1050's, wally 255, and supporting mods. Lately I noticed when I do pulls, at wot on full boost my afrs are high 12's to low 13's. They were fine before and I do not know why they are lean now. I pulled my injectors and cleaned them they were not bad at all. I ran seafoam through my tank also. Could I have gotten bad e-85? I have been getting t all from the same station. Any ideas on what else I could check to find out the root of this problem?

 

Having same problem. I'm going for a clean up on my tune soon. Re adjusting fuel pressure changing plugs and what not. Are you on speed density?

 

pull your injectors and inspect them. You might be getting gunk from the e85 and they could be getting clogged. Run a bottle of seafoam in the tank maybe that could help clean them out.

 

Have you checked your fuel pressure regulator and pump?

 

Check the ethanol content and see what it is now... if you were running it 2 months ago, it could have been E70, and may be back to E85 now, and that is why you are running a bit lean...As others have said check injectors, and also check for fuel leaks and pressure drops on the fuel feed line

 

Yeah im gonna get the tune checked out soon. Im running stock maf. Also running stock plugs.

Already did that.

Pump is fine, running stock fpr and hose is zipped tied on.

Yeah I agree. I need to get one of those ethanol testers. I dont think its leaking fuel. I am going to do a boost leak test at the same time as the tune.

Thanks for all of the input everyone.

 

Are you sure it's not the WB Sensor going out? Best way to tell is throw it on a dyno and see what actually going on.

 

WB is less than 3 months old

 

Ok so I did the boost leak test. All good. Injectors are pump are good also. E-85 tested good ethanol content. Im thinking I just need to add more fuel to my tune. Any other ideas to throw out there?

 

Have you tried dialing back the boost just a bit to see if that brings the AFRs down? If there was a major difference in temps between two months ago and now, you may simply be taking in denser air, causing you to go a little leaner than when you were tuned in the warmer temps.

 

Good point. I am going to retune in a few days and see if that will be the fix.

 

e85 tunes tend to run lean in cold weather. if temps have dropped since your tune, could explain the leaner afr. i typically richen my fuel map by at least half a point in winter.

 

That explains alot. I got tuned when it was a lot warmer outside. Thanks for that input.

 

Bumping this thread from the grave.

So this problem still exists. I recently tuned outside and it was about 105 degrees last week sometime. Afrs were spot on at right about 12.0 through WOT. Now a few days later I do a pull in the evening and AFRs are around 12.7ish throughout WOT. Anyone have an idea of what the problem could be?

Running v7 SD grimmspeed 3-port at 28psi stock ix turbo e85.

 

The lower temperature in the evening, compared to the 105 deg F you set your tune at, means that the air is denser and so your engine is actually getting more air. Unless you increase the fueling to match, this will make your AFR higher, i.e. leaner. E85 fueling is more sensitive to temperature changes than gas probably because of it's higher flash point and greater latent heat of vaporization.