A year ago this 4th of July, I was on my way to camp for the holiday. We had just started to come down a hill when the motor on my 2001 Dakota 5.9 just shut off. We towed it to camp and started checking the usual things and fuses. There was no spark, so we ran back to town and got a new coil. Replaced it and still only cranked. So we moved to the CPS. Still only crank. After day 2 of no luck, had a friend run me back to get my Cummins and trailer. Got the Dakota home and it still sits on the trailer to this day.

Only codes it is throwing are O2 sensors. 0031, 0051, 0136.

I have replaced:

All O2 sensors
The PCM
Camshaft/Coil pickup
CPS
Coil
Engine Wiring Harness

ASD relay comes on and stays on when cranking. (took the cover off to see it function)
Had a mechanic friend put his computer on it. CPS and Cam signal were there, and both were in sync. Grounds were checked when I got to the point I figured I would replace the Engine Wiring Harness. This is when I realized the injectors weren't firing. We thought they were.

I am out of things to replace and ideas lol.

Anyone have a clue what has happened?

 

Are you getting a 12V pulse across the ignition coil? should have 12V constant from the ASD on the red wire, and a pulsing ground on the black wire.

 

that sucks man,
hopefully you get that thing ignited by this 4th .

 

I have the constant with the ASD, voltmeter on the plug 11.5 v when key on, 7.2 on crank. I didn't see any pulsing.

 

is that through the ground of the coil plug? It should pulse on and off when cranking, that pulse is what fires the coil. Easiest way is to put a 12V test light across the 2 wires. Either it fires or it doesnt.

Aside of that, stabbing the coil wire on an insulated screwdriver and holding the screwdriver next to a grounded component is the more dangerous but more rigorous way to test for coil signal.

 

Yes that is the volt meter leads in the plug socket. I tried my test light both positive post on the battery to the ground on the plug. And plug positive to plug ground and can't get a light. Only hint of activity is on the volt meter. The test light is a standard cheaper indecent bulb unit.

 

If that's while cranking, then it's definitely looking like the PCM is either not sending a spark pulse, or not getting a crank pulse (and/or cam pulse).

Next step: Do you get 5 volts at both the cam and crank sensor plugs, on the chassis side? Should be the outer 2 wires. They share both rails, so they should get the same.

Next step (this can be a PITA): volt meter between the center pin of the crank sensor (plugged in) and ground. You should get a series of 5 volt pulses. 5.9 should be a pulse every 45 degrees of crankshaft rotation.

Next step (even more PITA): volt meter across center pin of cam sensor and ground. Should see a very slow 5 volt pulse. The reluctor "wheel" is 180 degrees wide, D shaped. so 180 degrees on, 180 degrees off (relative to the camshaft/distributor).

After all that, if you are getting a good signal from both sensors and no spark or fuel injector pulse, it's PCM. If you are not getting voltage at the sensors, also PCM. IF sensors are getting voltage but not putting out a signal....dead sensors.

There's a starting point for you.

 

Was the PCM new rebuilt or junkyard?

Many have experienced problems with rebuilt PCM's and junkyard PCM's that don't 100% match their model.

 

i fought for about a year with my pcm... had a iac take out the pcm. replaced iac, and had pcm fixed.
ran for a few days and the the pcm crapped out again.. sent off had it tested, they said no issues.
replace a ton of parts.. came down to bad pcm again.. witch took out my solenoid in the trans.
replaced pcm with ebay model, and replaced all electronics in the trans at the same time.
not having issues except for an occasional cyl 5 missfire. only thing i can think of is that cylinder is loosing some compression.
i can live with it.