abmotorman

OK, I’m officially perplexed. Port engine stutters especially noticeable during acceleration. Here is the list of new parts. Cap, rotor, wires. Swapped MAP sensor, Ohm the throttle position...working. 2 weeks ago had it checked for active codes none. Checked spark on number one, very stable advances the same on both motor after a comparison. I thought it was going to be the ignition pickup. Does the module send the ecm the signal to fire the injectors??? It really sounds like the engine is being told to run this way. Almost like it is a basic run mode?? Oh and changed the water separator 2 weeks ago (no sign of water).

hallj

Have you swapped ECUs?

Jeff

abmotorman

Not yet. Try it tomorrow. Did a compression test. Alls well 160psi. Still wondering in the module controls fuel map signal since the ecm must get its signal from their.

abmotorman

Actually going to try switching injectors out. Hear a strange thumping sound in exhaust manifold on one side of the engine. Starting to think I got a injector staying open???

abmotorman

For those following this saga. It turns out after checking and comparing the timing of both engine it is safe to say the timing is jumping around more than usual on the port engine. Changing the pickup tomorrow.....if it is in stock. Oh yes, i switched the ecm's air idle motors also.