I have a miss which occurs after the engine is warm, it is not steady but a hit and miss type, Changed injector o rings and harness assb. last year and have a new return fuel pressure check valve installed. It seems to occur when the air compressor is charging the system. I don't see how this would have an effect on the missing. Any ideas
ive seen a similar problem with the same engine in gillig transit buses when it pulls up a slight hill. itll feel like a slight hesitation and wont ever set a code. if youve got a scan tool you can check the injector solenoids and listen to them carefully. often with a problem like this youll hear one or more of them sound a bit weaker than the others.
On an EGR 466, I have had a wire going to #1 injector that had rubbed through and was intermittently shorting to the inside of rocker cover and causing the occasional miss. Most likely to occur if one of the six plastic wire holders is broken or out of place.
I've been fighting an erratic miss for several days now on a '98 466E. FINALLY got a CMP code, replaced the CMP sensor and all seems good now. With no codes showing, I was thinking fuel pressure issue, but wasn't finding anything wrong.
I changed the cam sensor and after the relearn the engine ran fine, ending up removing one of the shims from the previous install. will see what happens