[john51md]

Originally Posted by Tinman238

OK, I've been dealing with this problem for 3 weeks now.

First it died and would not restart. No codes.

good fuel pressure
good spark
new crank position sensor
new fuel filter - needed it
new plugs and wires - needed them
new coolant temp sensor
plugged off EGR
new O2 sensor - due
pulled ICM and had it checked - checked good

Still would not start

new ECM - Ah haaa!!!....it runs - badly - but it runs. Had to floor it to start it, pops, erratic idle, won't consistently stay running.

Hmmmmm.....checked for vacuum leaks, couple of questionable hoses, replaced them. Decided to pull the intake for two reasons: replace the o-ring on the oil pump drive and check for intake gasket leaks. Found no intake gasket leaks. While I had it apart, I replaced the PVC hose with a new one. Upon reassembly, it runs exactly the same - like crap. No codes other than 12.

Decided to hook my timing light up and, one at a time, put it on each plug wire. Timing flashes are inconsistent. When the engine is speeding up, in its errant speed fluctuations, the flashes are consistent. When the engine is slowing down, the flashes stop or are much less often. So...., this tells me that I do not have consistent spark. So I replaced the center coil and checked again. Same thing, even on the new coil. So I replaced the ICM (even though it checked good earlier). No change, no codes (except 12).

My thoughts are:
The crank position wiring has issues, or
the new crank position sensor is bad.

Any ideas out there?

What about Throttle Position Sensor?