Hi all,

First post here. I bought a 99 24valve about 4 years ago, completely stock, still is today. With having another work truck around it doesn't get driven much. When I bought the truck, it ran perfectly, started every time I turned the key so on and so forth. After sitting awhile, it started acting a bit weird and through a code for the crankshaft position sensor, I replaced with one from Autozone. Tach would die, and stutter/ reduced power, but it would run. Just not right. I did notice when I replaced it looked like it had been replaced before in relation to the grime on the block. Ran well for a bit, then the same thing started happening, I thought I would try change the pigtail to the crank sensor and check the wiring, I did that. After this I noticed the truck would start cold and but after driving enough to warm up the truck it would not, crank and no start. Well enough of that kills the battery, so I replaced the batteries as they were getting older anyhow. Still crank no start, still a code for the crank sensor, but now the fuel pump wont run. When bumping the starter, I get 8v on the harness to the fuel pump but then it goes away (stock fuel pump on side of block), I took the pump out and tested it, it runs when hooked to a 12v battery. Is my ECM failing?

I am planning on getting a different fuel pump as I've read the stock ones don't supply enough psi to the vp44.

I'm not versed with these trucks any help would be appreciated.

Thanks!!

Edited May 6May 6 by MarkR1991

I would suggest a AirDog 150. I just got done with a custom install on Thor.

https://mopar1973man.com/blogs/entry/18-the-stealth-airdog-on-a-3rd-gen/

Edited May 6May 6 by Mopar1973Man

I replaced the lift pump,still having the same issues. I have no voltage to the lift pump, tested out of the truck and works fine. I'm not getting fuel. With the ecm and pcm looked at by auto specialists I am a bit stumped on what to look at next. What should I be looking at next? Vp44?

Thanks

Double check the black/white wire that grounds behind the starter. This is the ground lead for the lift pump and fuel heater. If you bump the starter there should be power on the the other wire in the plug but the ground might be dead.

41 minutes ago, MarkR1991 said:

I have no voltage to the lift pump

How are you checking voltage for the lift pump? Where are your test leads connected?

Ignition key on - lift pump runs for 1/4 second

Bump start, leave ignition key on - lift pump runs for approximately 20 seconds

The ignition key must be turned off between bump start tests.

• John

I would suggest a Cummins crank sensor they are not that expensive. We have loads of issues with non genuine CPS sensors over here in the UK.

Also as mentioned bump the starter and your lift pump should prime for 20 seconds or so