Intermintent starting problems
 

99, Fass pump and boost fooler.
I got stuck in town because the SOB would not start tonight. This has been an on and off issue but has gotten worse in the colder weather.
Here is whats going on.
I could turn the key and hear the short lift pump cycle. Bump the starter and the pump does not run. After an hour of messing around and having my father in law make a half hour trip with his wrecker to rescue me it started.

While trying to get it to start I ran a jump to the lift pump and it ran just fine but the engine would not start like that. At least I know the wires are good going back.

Do I have a bad ECM ? It will be plugged into a tester tomorrow. Any other suggetions? I see conflicting info on here. I see some refer to the PCM as turning on the lift pump and some refer to the ECM. Which is correct?

Thank-you

I would start by getting a fuel pressure gauge to see if the lift pump is the problem. Other than that it's probably the injection pump as I've not seen many ecm's go bad unless the alternator went nuts and caused an over voltage condition. The diesel does not have an ignition. As long as the injector pump is pushing fuel through the injectors the truck will start. I don't know how much the ecm can defuel the VP44 injection pump, maybe others can chime in?

IIRC the PCM controls trans shifting and the ECM engine functions, including the LP operation.

When my ECM went out, it would not start the truck and allow it to run. It would cough and sputter and then quit. After an hour or so it would start and run rough enough to move it but not drive it at any normal speed and usually choke out. I know this because the tow truck left it in an unlit alley behind the dealership in kalispell and I didn't want it left overnight there with my tools in it. When we went to tow it around it started and ran like hell but I got it in front of the service bay....

Not saying that is your problem, but you should do as Dane suggested and check fuel pressure, fuel lines, filters etc, then get a scan..