Could someone take a look at my log?

[tb13]

I'm just curious what others make of my datalog. Let me say first off that this is not a cobra, its a 2004 saleen mustang with a series 4 supercharger. I am getting an email tune from a pretty reputable shop and I'm just a little concerned. We are on the 6th revision right now and we can't seem to get WOT dialed in. Car drives ok except for WOT where it is very rich, pretty much staying in the low 10's. My tuner can't seem to get this dialed in and keeps saying he thinks I may have a fuel issue and now is saying he is seeing an inconsistent maf signal when he had never said that before. Could someone please take a look and let me know what you think?

Log location: 2004 Saleen Log 8-27 - Zoho Sheet

Thanks

 

[WaffleMan]

I am no tuner, I only tune my own car so take this for what its worth.

STFT - Short Term Fuel Trim
Closed loop - car is making fueling corrections and going off of the O2 sensors. STFT of 1.0 is stoich, 14.7:1 AFR on pump gas or 14.1:1 on e10. >1.0 means car is having to pull fuel to get to commanded value, <1.0 means it's having to add fuel.
Open loop - car is ignoring O2 sensors and strictly going off the commanded value in the tune, using the maf transfer function. You know if you are in Open Loop when STFT 1&2 are stuck at the same value and not fluctuating.

There is a area in the log where it looks like you slowly roll into the throttle, from time 8.5sec to 12.1sec, where the car stays in closed loop. If you look at the short term fuel trims they start to deviate from 1.0 lambda starting at 600maf cts and are 1.16 lambda on bank 1 and 1.09 on bank 2 by 941 maf counts. This is saying the car is having to pull fuel to get to the commanded value, in other words the maf transfer function is off from 600+ maf counts.

So when you go WOT and the car goes into open loop, .82 lambda is being commanded, which is 12.0:1 AFR. But since you are 10-15% rich up top you are in the 10s AFR. Hope this makes sense and is of some help.

Rest of the log looks good, I don't see an inconsistent maf signal and fuel delivery looks fine.

 

[decipha]

if one bank is removing 16% and the other removing only 9% then you have a 7% difference between banks, thats not good if your over 1/4 throttle or so where the injectors have already gone linear

tell your tuner to yank the timing down up top and leave it in closed loop at wot, do 1 pull from idle to redline and let the o2s see the per bank fuel correction. Apply the correction re-enable enrichment and your fuel is dialed in.