Well i had my car tuned on wednesday made 449/325 @24 psi on E85. AFR was 11.6-12 did some runs with a friend that night. The next day i filled up and did some more racing. I looked at my wideband during the pulls and realized afr was @10.8. I then ran the car to very low fuel level and refilled it again then went out to a local meet and did some more pulls. 10.3 now. I have parked the car and started looking for boost leaks and I can't find any. Any thoughts would be greatly appreciated.

 

Have you been testing the E85 during each fill up? I think people underestimate the vast inconsistency among fuel stations and bulk station fills. It is important to test each batch of fuel you get with E85. This is why it is worth the extra money for a Ethanol Content Analyzer.

First thing I would have done would have been reading the plugs.

 

I have not tested the e85 content. Last year when my car was running I never had any issues with it. I guess that doesnt mean this year couldnt be different. I will pull the plugs when I get my tools back from my friend.

 

was the tune touched up on the street after the dyno? I found often times, it will be a bit richer on the street when its presented with a real load, moreso than some dynos can simulate or at all.

 

Like 98vtec states I normally have to street tune mine after getting it off the dyno as well, which drive me nuts. It would not hurt to check everything out like fuel pressure, has the temp changed much since your dyno run?

 

We did not clean it up on the street after dyno. Temps are about 15* warmer than dyno day. My injectors were pulled and stored for about a year. Car ran on e85 before. Could they have possibly been slightly clogged and getting cleaned out as I drive it? Seems to be getting richer. Refueled today and it tested e83-84 from the same station it was tuned from.

 

My couple hundred dollar wideband alway read different from the dyno wideband . Just put it back on the dyno if you are concern. I have used a Couple wideband that Read different from each other so I alway leave it a tap rich to be on the safe side.

 

MY Aem fail safe AFR just malfunctioned on me, had me thinking my motor was running extra rich it was just the AFR gauge sent it to AEM they repaired it but i sold it after and baught a Inovate mx-L AFR gauge its awesome! so easy to wire up and it has the most accurate AFR reading!

 

The gauge could be off a little but the car doesn't feel the same. It hiccups when I shift into the next gear when I'm doing pulls. I raced my friends 600hp C63 the first night I got it back and pulled him hard in 4th once I got traction. Put some et streets on it the next day and raced him again and we were pretty much dead even.. Talked to my tuner and he's not very happy that this is going on. When I get a chance I'm gonna take the car back to him and see if he can figure out the issue.

 

If it is hotter outside and fuel trims are not adjusted correctly this will happen.

I have also seen premature sleeve cracking richen up afr values... just a heads up.

 

I would hope its not a cracked sleeve.. It has Benson sleeves