Rage

Good point. I route the o2 sensor cable such that ignition noise is not recorded with few exceptions and for those I can tell what is noise and what is the base signal. #7 does have some ignition noise at high rpm but the base o2 signal is evident and still way leaner than the others at that high rpm. The computer voltage is too low to influence the o2 signal.

TWIN-SPINS

recheck any sensors or vacuum hose,,,near 5 qnd 7 cyl,,,could you have a air leak????

Rage

Well I swapped the injectors and reran AFR tests on the four odd bank cylinders. Nothing has changed so it is not the injectors. Vacuum leak is unlikely and I am not sure if it would even have any effect on a MPFI setup like it would on a carburated or SPFI system where the fuel is mixed with the air before entering the intake manifold. I just do not know but would seem like not. I do have earlier AFR data on all eight cylinders where this latest lean #5 and #7 cylinder condition was not displayed but the ECU did not have the latest ECU reporgram. TBC

TWIN-SPINS

what if you sprayed carb cleaner around 5 or 7 cyl,,,while you do one of your test,,,,if you did have a leak wouldnt it drive the ratio rich,,,and maybe then you could say you dont have an air leak

Rage

Well sorry I can not be sraying anything going down the lake at WOT with the engine hatch closed. What are yiou thinking?

TWIN-SPINS

at dock ,two guys ,hatch open,,,do your test,,,,anyway you can ,,,just trying to drive the the 02 sensor rich to see if it is an air leak,,,,,,you wont need to look at the other cyl just those two,,,this can be done at the dock at idle

Rage

Ok, I get the picture.