Engine will sometimes not rev

[Pete_89T2]

Originally Posted by Rotary91

Talked to a good a friend of mine, he believed it is not the OMP because it would throw a code and it will only cause limp mode after a while, mine starts right away. We think it is the MAF, since he had similar problem and his MAF was the source, he also didnt have any codes when the MAF went bad. Time to check MAF wiring.

Your friend is wrong regarding the OMP. When my old wiring harness was going flaky, I discovered that even intermittent open circuit associated with the OMP wiring, either the OMP stepper motor or the OMP position feedback sensor, would both trigger the CEL and force the limp-home mode every time.