Hey, I was hoping I could get some help. I'm really losing my mind with this car and am fresh out of ideas.
I keep throwing lean codes for multiplicative fuel trims. After ten minutes of driving my multiplicative LTFT's will be almost maxed out sitting around 20%. Additive stays very close to zero.
This makes me think that my issue is not a vac/boost leak as I feel like it'd have to be a huge leak to throw LTFT off so much and I also think it'd make additive ft's worse than mult.
However, the company who will be tuning the car said it sounds like an intake leak. I've checked and checked and cannot find one. Well, I found a couple minor ones but fixing them made no difference.
I had been thinking the MAF may be the culprit but it's a new (not reman) Hitachi with only about 3k miles on it and it appears to reading proper g/s. At idle I think it's around 5g/s and WOT around 340, which sounds about right to me.
What I think is interesting though is that my car's fuel trim's stay within spec if I drive with the MAF unplugged. This brings me back to thinking of a boost leak.
Here's something else that's interesting. I've cleared faults a number of times and each time I do my idle AFR stays around 19. I can't believe a car will even idle like that. Sometimes it goes back to normal as soon as I start driving. Sometimes, I can cruise and it will stay around 16 or 17.
However, what always makes AFR go back to stoich is a WOT run.
I guess I should probably give more specifics about my setup too lol.
It's a 2000 Audi S4 with an F21 FrankenTurbo kit purchased from Epic Tuning Group. I'm using their 85mm MAF housing with a new Hitachi MAF, 034 conversion harness, EV14 550cc injectors, Walbro 400lph drop in from ProjectB5, stock ignition system (coils only about a year old, BKR7E gapped to .028, and OE ICMS), JHM FMIC, Zeitronix Zt-2, STE PPD for AFR/logging, rebuild 01E from AdvancedAutomotion, FX400 with Fidanza aluminum flywheel.
I have a thread started about this on Audizine already:
http://www.audizine.com/forum/showthread.php/591030-Stage-3-%28F21%29-Lean-Problems?p=9651407#post9651407Also, I took some logs today using ME7Logger. I haven't quite figured out how to make things look nice with graphs yet but here's the .csv if anyone could take a look:
http://www.datafilehost.com/d/0a30320bAny suggestions or questions please just let me know.
Thanks a lot for any help.