I have a 2003 Bonneville SE and it is running really rich. See mod list below. It doesn't seem to matter if I have my ZZP pcm in or my stocker, I pretty much get the same results. I put my stocker in Sunday and it seemed to get better for a while and slowly started to get rich again. Anyone have any ideas?

Thanks

Shaun

What are your symptoms?
(Or, by what method are you measuring A/F and/or trims?)

Very rich gas smell, bogging and loading up when on the gas hard, poor gas mileage. Using DHP powertuner scantool and fuel trims are way rich. -25 sometimes when idling and -15 to -7 while driving.

Can you verify with the PowrTuner that your MAF sensor is working properly?

Also check your O2 readings from the sensor.

A bad sensor will default you into a rich mode.

If it was a bad O2 sensor or MAF sensor, I would get an SES light and a code wouldn't I?

One or the other could be working poorly, but not "broken" enough to set a light.

Log a scan, making sure to capture A/F, ECT, FT Cell, Gear, IAT, IPW, KR, LTFT, MAF Hz, MAP kPa, MPH, O2, RPM, Spark, STFT, and TP%

EDIT: capture IAC, also...a malfunctioning idle air controller can cause chronic richness

The powertuner I am using is set up for a 1998 grand prix and won't read my pcm. I am able to use the scantool but I have very limited features to view. I have LTFT, STFT, MPH, FT CELL, AND IPW and that'* about it. I will see if I can post the scan for you.