I have a 2004 new body style 4x4 and I’ve been having some hard to chase issues lately. I went in and did a bunch of valve train work put it all back together and the truck started right up. It ran just fine for about two minutes of idling and then all hell broke loose. It started marketing a bunch of terrible noises and started to shudder so I turned it off. Went to start it again and it would run for a second and then stall. Started it again and gave it gas to see if that smoothed anything out and as soon as it got to about 2500 rpm the truck cut off. No sputtering or anything just turned off. After this the truck would crank over but wouldn’t start. Ended up putting the battery on a charger for a few days and reinstalling it once we did this the truck started up with all the racket it was making before. We ended up just letting it run for about two minutes at 2000 rpm and it smoothed out stopped making noise an would idle just fine. The truck was throwing a bank 1 cam position sensor fault but would run regardless of the sensor being plugged in or unplugged. The truck would rev just fine with now problems so I decided to drive it around the block I was able to idle out of the driveway just fine. I gave it gas got up to 2500 rpm and it cut out just like it did before. Now if you let it sit for a day it will sputter briefly when you try to start it but then nothing. It just cranks and cranks. It will not start with starting fluid so I’m guessing no spark. The fuel pump primed and the driver has been replaced so it’s getting gas. The pcm has good grounds and is getting power. All of the ignition fuses are good but when measuring voltage on the COP connectors from the hot to ground on the chassis I’m not getting any voltage with the key in run any help would be greatly appreciated! Could it possibly be a bad pcm, i there any way to test the pcm and anything else to look at before replacing the pcm?

 

what happened to the shudder and massive valve train noise ? You don't think this is related to valve timing issues ?

 

 

 

Was the crank sensor tone wheel reinstalled correctly with the teeth facing the timing cover? If it was backwards the teeth will dig into the chain. No teeth=no RPM signal.

 

 

 

 

"Testing" for a bad PCM usually means ensuring all applicable PCM inputs and output circuits are good. If there is an input problem, then there will most likely be an output problem ("Garbage In->Garbage Out") and of course if there is an output circuit problem, the PCM can't control that circuit.

Do you have a scan tool that is capable of reading PID's? IE Forscan or Torque? If so, connect it to the truck and see if the RPM PID reads anything while cranking, this should tell you if your Crank Position Signal is reaching the PCM.

 

 

 

 

 

If you do not have power on the "hot" side of the COPS, the engine will never run. Since you failed to identify what engine you're working on, it's not feasible to try and look anything up.