I can make my trims perfect, but they start to really drift off after a few days. Has anyone ever had this problem? I have another thread about my car getting lean at wot. I think it may be connected. Also, can fuel trims affect WOT open loop fueling at all?

Thanks

 

What scaling and latencies are you using?

 

gas or E85?

 

E85

Scaling is 713

Main Latency

1.056 at 11v
.744 at 14v
.528 at 16v

Even if these numbers don't look like they should, the car was extrememly happy with them a few months ago. It seems like it wants new numbers every month. I richened up my fuel map back to 12.0 because I noticed it had shot up to over 13.0 at WOT over a months time. Now it is down to 11.6 at WOT.

 

Any ideas? The car just goes back and forth on what it wants for fuel. My trims will drift away no matter how perfect you get them. It still seems like this may be affecting my open loop fueling too.

Thanks

 

On another note too, how consistent does everyones tunes stay with temp and weather changes in general? WOT AFR ect...

 

could your e85 mixture be changing........

usually from what i see on my car is that sometimes tank to tank my mid trim will swing one way or the other depending on the ethanol content, and my wot does change - usually I just have to make a slight scaling change (rich or lean) and the fuel map and trims are back to where they were.

 

Well it was the same tank of e85 is the thing, and I would think it would be going richer if anything this time of the year. Also, any opinion on those scaling and latency numbers?

 

I guess at this point I just really need one question answered. How consistent does your guys WOT AFR stay after a tune?

 

Keep in mind that there is sort of a 'known' problem with E85, where some stations seem to have a lot of 'gunk' in the fuel which precipitates out due to the lack of solubility in ethanol. There have been several threads on different boards about it, usually entitled something like 'injector gunk' or similar.

There have been a few members on here that have seen their AFR start to go lean after a certain amount of time switching to E85. It could be the precipitates clogging the fuel sock going into the fuel pump and/or the injector gunk.

There was a chemist that analyzed the stuff on some other board and basically it was soluble in gasoline, but not in E-85. So, if this is your problem, maybe running a tank or two of gasoline will clear it up. Or, if you are curious enough, take a look at your fuel filter and/or injectors and see if you see anything.