Copper plugs?

 

I'm not very familiar with the open/closed loop stuff with 02 sensors, but sounds like an issue when the ECM should be in idle mode, I know on diesels, the variable throttle system and idle system on the TPS are two different maps, controlled by the same sensor, it uses a certain voltage to trigger the idle fueling map vs above a certain voltage is uses the variable throttle map. I know the TPS was replaced, could be new faulty, or wiring, or maybe even PCM?

 

yes copper

 

Did you swap out the PCM????

 

yes with the same issues .if you follow this thread back you will see everything I have tried or replaced

 

Yeah, I saw that, but, wasn't sure that you actually swapped it, so I asked, just to be clear.

Does anything change if you disconnect the front O2 sensors?

 

no change have tried that as well.. I am just stumped..

 

have you tested oil pressure at hot low idle, and hot high idle with a mechanical gauge?

 

Not sure what the correlation there would be.......

Single plug per cylinder on this engine??

 

Yes around 25psi low and 41psi high