01 2500 HO 6 speed 2wd, stone stock, except for moving stock lift pump back by the tank at 80k, replaced pump at 129k for preventative maintenance. Now at 214K. Never wrecked, never seen salt - Florida vehicle its whole life. Died in my driveway, as if the lift pump was dying - at first I figured either a voltage issue to the lift pump or the pump itself. A few weeks back, I noticed WTS light not coming on very infrequently and still being allow to start the motor. Not sure if that's relevant.
Back to being dead in the driveway - cycled the pump as if filling the filter after changing it, ran for a little while. Shut it down, try to start a few days later, no start. Lift pump sounded sick, like it was laboring. Swapped out the pump, replaced the 'extension cord' needed to move the pump, new pump sounded much worse (conclusion - new Carter pumps made offshore are junk). Put a gas motor code scanner on it, NO CODES, Passed. Removed the ecm, have never had the harness off it, pulled harness, no obvious corrosion on pins or connectors. Cleaned ECM mounting points, made sure good ground all the way back to the battery. Cleaned harness connection lift pump. Re-installed old lift pump, sounding better than new one. Checked fuel pressure at the VP44 while pump cycling (as if filling the filter) - 13.5 psi. Cycled the key on-off,on-off, on - codes on the odometer - P PCM _ _ _ _ _ _ P Done P ECM _ _ _ _ _ _ P Done - again, no codes. Charged the batteries, am getting WTS light, still won't run. Cranks fine.
What to check next? Especially with no codes?

Google Cummins FCA - Fuel control actuator. might be your problem.

Is it coughing smoke? color? or it is like trying to start with no fuel?


Also outside temp?

Air in the injector lines?
I can't bring myself to ask if it fires with ether...

Ourside temp hi 50's, low 60's. WTS light is coming on, then going off, before I try to crank. Doesn't pop or spit like it's getting some fuel, don't see white clouds out the back.

No, will never try ether on a diesel. I cycled the lift pump a good dozen times, shouldn't be any air, although I do have a trickle of fuel coming out the handle for the drain valve on the filter, which I need to address, just not sure how yet. Haven't taken it apart. Had the filter assy out to get at the ECM. Washed it off in the parts washer and now I notice the leak.

That part seems to be on 03 and up common rail motors...mine's an 01 with a VP44..

I would crack open the injector lines and see if you are getting fuel to injectors.

If not, I would crack open the fuel line going to the VP pump and see if the pump is getting fuel.

This era of separate ecm and pcm required a “good” scanner to communicate with the two controllers. Key cycle deal was handy for sure.

However.... iirc even a cheap code scanner can read the pcm, and even though you can’t read the ecm codes/data, it usually sets a companion code in the pcm telling you there’s a code in the ecm.

That said.... how much fuel in the tank? This era was known for “1/4 tank syndrome”. Fuel level sensor fails and will read 1/4-1/8, when actually empty.

Hopefully you have no dtcs, if so do what was suggested above and loosen 1,3,4 injection lines and crank away to see if it will prime. If you start getting fuel at the loose lines tighten them and hopefully it will start. If it does start and run you’ll prove that it’s mechanically able, but you’ll need to find where air is getting into the system.

Follow the fuel. Start at the tank make sure you have good fuel in it. Make sure the filter has fuel to it , then make sure that the fuel is getting to the pump. then see if the pump is pumping fuel to the injectors. If no fuel to the injectors and you have fuel to everything up to the pump and the right pressure to the pump your pump is shot. Also don't be afraid of ether just don't abuse it. just a sniff. disable the cold start system and give it a quick shot in the air tube at the filter. that truck should not need anything as a cold start aid in florida at that temp. A cummins will start at just about any temp when all is right. vp44 pumps are known for failure. If all that checks out it may have a bad crank sensor you may need a good scan tool to help your diag. Diesels are simple

If you have a leak at the filter, wouldn't mean your main pump will be sucking air?

The system and injection pump is fed fuel under pressure by an electric lift pump. So no it would not be sucking air. The lift pump also must maintain a specific pressure to the injection pump because the fuel is also used to cool the pump and its electronics. Low fuel pressure is the main cause of pump failure on vp44 pumps.

Leak at the filter could certainly cause a no start after sitting on a VP era truck.

The factory intank pump 'upgrade' is junk. After putting in a fuel guage in my '01, I had 12psi idling. Driving it (truck unloaded) would drop the psi significantly. At 7/8 throttle, it would be at 0. The injection pump needs to see 10psi minimum at all times. This will definitely damage/overheat an injection pump.
Pulling a trailer with your factory intank pump, I'm guessing your injection pump has possibly expired.

injection pump !

Huge myth

The culprit? The lousy drain valve on the filter. Dribbled out the top, couldn't see it due to the trail of gunk on the filter housing (no doubt caused by the dribble...). Lost prime, allowed lots of air in to the system. After replacing the valve and cracking loose a few injector lines (something I have NEVER had to do in nearly 20 years after changing a filter to bleed some air), it came to life. What I could not figure out was why the lift pump was acting up - as if it were dying or had a voltage problem.

lift pumps can do and sound weird when they are pushing air because its compressible.

While I understand the “theory” of moving the pump, I’ve seen a lot of issues with pickups over the years that have had that particular mod done. From poor fuel line connection, to too small of wire and corroded butt connectors. I still run a pump in the stock location. It’s easy to get to and by monitoring my fuel psi I should be able to tell if it gives up the ghost. I’m only on my 2nd lift pump from the oem unit that started weeping after a year of ULSD (Cummins made an upgraded diaphragm).

FWIW I see about 12psi at idle and on a long steep grade towing it can drop to 3-4. Not worried in the slightest.

The intank pumps (retro-fit kit) I’ve tested over the years would drop close to zero, but rarely went into a vacuum. The ones that did go negative I’d often find the strainer/inlet in the pump loaded with debris from “dirty” fuel sources (in bed steel tanks, steel farm tanks, construction site vehicles). Fuel volume to the VP is much more important than psi.

As far as the theory, I understand it to be the same reason that electric pumps are near the tank on a drag car - electric pumps do better at pushing fuel rather than pulling it. The shorter the straw to start the siphon, the less the pump has to work, the longer it will live. And mine got a 1/2" line from the pump to the filter and from the filter to the VE44 at the time. Mine is on the inner frame rail about 8" in front of the tank. I cut the stock fuel line there, bent it outwards, then plumbed the moved pump to the stock line back into the tank. From the inlet of the pump forward it's all 1/2".

With my 02 I put a large Carter pump in line as far back as I could get it. It worked great. I know my son had an ECM failure on his 01 HO I believe it wouldn't start and it was a bit hard to find another one.