I have one area in the BLM that is running fairly lean 139 to 142. I've bumped that area up a few times, but it still is lean. One other thing I've noticed is that area has a very wide deviation - like up to 33, but several cells at that rpm have over 24 deviation. The cells are 1600/2000 RPM X 36 to 52 KPA. Any thoughts or should I just keep tweaking? I'm looking at running average for the BLM. Other cells are typically less than 5.

One other thing, running ScannerPro, What is the difference between running average and history average? The 2 values are different by a factor of 10 in one cell.

 

Are you running headers? that happenned to me as there was a leak at collector flange to ext pipe. Any leaks in ext may be picked up at NB02 sensor or WB for that matter. Only other thing is a huge cam(reversion).