"At wide open throttle my right bank gradually from the time I hit it went
lean, from 900Mv to 4mv in whatever gear. The next gear the right bank
stayed low in Mv but the left was relatively OK(getting leaner but not
nearly as bad as the bank2). I think the Fuel pump may be the culprit. but
why one bank and not the other? The interesting thing is @ WOT the 02's are
running in an open loop mode, but yet they are correcting for a lean bank @
WOT. The bank that the 02's drop out from the pulse width is increased by
about 3ms over the other bank.
My part throttle fuel curve is good, the problem just happens at wide open
throttle. The 02's are moving all around dunring reg driveability but they
only drop out @ WOT. I have tried adjusting the fuel and timing, but still
no change. i have changed my injectors, checked for exhaust leaks, have new
o2's that have 1500 miles on them. No difference.

 

Have you checked your fuel pressure at WOT? If thats fine then I don't know what your problem is.

If the pressure is low and you do not have a power adder like supercharger or heads/cam then I would say a clogged fuel filter. If you do have a power adder than I would have to ask if you have an inline fuel pump. If not, you probably need one.

Hal

 

Hal has good questions for diagnosing.

As for it correcting the lean problem at WOT which is considered "open loop," I've seen the same thing. When my fuel solenoid stuck closed on my n2o system, I could see the O2 values drop and the BLMs then shoot up to try to correct it.

So, it appears the PCM does try to correct overly lean running at WOT. I've seen < 128 short-term BLMs at WOT too, so it seems it also corrects overly rich.

 

i have a heads and cam combo on my car. my fuel pressure is good at WOT.