Car runs extremely lean 16 then after running it hard it goes way rich 10 is this cause the temp is getting hot and the engine is trying to protect itself?


97cavalier

More info. Mods. When exactly is it running lean?



FU Tuning

from about 6 to 8000 rpm wot, high comp pistons, w41 cams, .20 shaved head bigger tb gutted crank bored 100 over total seal rings oil pump swap


97cavalier

What tuning has been done already? With what program?



FU Tuning

Is 16 really "extremely lean"? 14.7 is perfect A/F ratio....i think 19-20 would be "extreme"

95LsCoupe wrote:Is 16 really "extremely lean"? 14.7 is perfect A/F ratio....i think 19-20 would be "extreme"

Yes for WOT 16 is very lean.



FU Tuning

oh true it doesnt say at wot my bad

we'd have to see a .log and a .cgf file of it happening.

is this all at WOT? or cruising in open loop as well?

Lots of things can effect it.

How is it tuned? are you using HP Tuners? Did you double check your IAT and ECT gain and and Mult. Tables for anything out of the ordinary? Those change/pull/add timing based on IAT and ECT......and timing effects A/F ratio.

You sait it's between 6000k and 8000k rpm. What is the IAT and ECT temps between pulls? there has to be something going on to make the A/F ratio change that drastically between runs. I'd look into the temps and what the IAT and ECT spark tables are set at.

Is the op speaking English?


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