Typical 24v being temper-mental..

Lil' Dunbar

Lil' Dunbar

The better looking Dunbar
Joined
Mar 3, 2008
Messages
105
Alright so heres the deal.... My 99 is being temper-mental with startup. I live in Georgia and temperatures right now are ranging from 30-60 degrees. Sometimes when I turn the ignition on my 'wait to start' light stays on for a little bit, letting the grid heat up.... normal behavior. Then when I crank the truck, it fires right up. However, sometimes the 'wait to start' light doesn't come on with the first turn of the ignition like its supposed to and I don't hear my (stock and most likely original) lift pump prime the injection pump. When this happens if I try to crank the truck it just sits there and spins as if the lift pump never even comes on. But if I cycle the key off and back on again it cranks right up. It never takes more than two cycles of the key to crank. No more white smoke than usual with a cold start so I don't think I have an injector leaking down. So my question is why is it doing this all of a sudden? It started about a week after my last fuel filter change. Could my lift pump be going bad? I can't think of anything I could have done wrong on the fuel filter change, I've done it several times on this truck with no issues. Any suggestions are welcome because I'm baffled at the moment. Thanks.

Jordan
 
If you are NOT hearing the lift pump come on, it likely is an ECM issue. The driver circuit is known to go out in them with age. Easiest fix is to tie a relay into a keyed hot and be done with it. I like the ABS power circuit since it comes out at the upper driver side loom.
 
I am having the same issue. ECM is what I've narrowed it down to. Mine also has half power until it warms up. It's the VP Voodoo!
 
Check your IAT sensor. It controls your wait to start light just rule it out. but it does kinda sound like the ecm or your key on power
 
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Found another thread on a website about this same problem. Apparently its popular in 99 models. A few guys said they just kept running the truck as is and it never got worse. Ive found that if when I first turn the key and the WTS doesn't come on, if I just wait until all the lights on the cluster go off the WTS light will come on a few seconds later without having to cycle the key again and it cranks up fine. Just takes a little longer to start the truck. Most of the guys commenting on that thread said that it only got like that in the winter. So I figure I'm just going to spend my money on a raptor 150 instead of trying to solve this. That way I never have to worry about being stranded because the raptor hooks straight in to the battery. So basically Im using this as an excuse to upgrade my lift pump :ylsuper:
 
Raptor 150's are strong lil lift pumps. Ive had mire for about 40k and its still running strong.
 
Lil' Dunbar said:
Found another thread on a website about this same problem. Apparently its popular in 99 models. A few guys said they just kept running the truck as is and it never got worse. Ive found that if when I first turn the key and the WTS doesn't come on, if I just wait until all the lights on the cluster go off the WTS light will come on a few seconds later without having to cycle the key again and it cranks up fine. Just takes a little longer to start the truck. Most of the guys commenting on that thread said that it only got like that in the winter. So I figure I'm just going to spend my money on a raptor 150 instead of trying to solve this. That way I never have to worry about being stranded because the raptor hooks straight in to the battery. So basically Im using this as an excuse to upgrade my lift pump :ylsuper:
Click to expand...

Exactly what mine does. Just takes a bit extra time. I'm trying to locate another ecm cause it does get frustrating in drive thru line and around the farm.
 
My lift pump doesn't prime sometimes, but most of the times it does. Been doing this for a very long time now. I just run it. The small research I've done says ECM, but I can't pin point it yet.
 
Yeah I've read where a few guys took their trucks in and had them try to figure it out. They just flash the ecm which fixes it for a little while, but not permanently. One guy took his to Cummins and even they couldn't figure it out.
 
http://www.justanswer.com/dodge/2smmk-2001-dodge-cummins-sport-edition-coming-home-towed-ecm-harness.html

here as well, except I think the Tech is wrong, the ECM- not PCM- controls the fuel pump , as shown here.
ecm6.jpg


Also, check the ASD relay ~~~http://www.cumminsforum.com/forum/98-5-02-powertrain/223918-asd-relay.html
 
Headcase98002 said:
Here is a complete diagram.

Click to expand...


Saved this for my personal stash, very nice! Thank you. On second thought, the PCM shows a trans temp sensor, wonder why we cant tap that internally with our edges like the boost? I'm sure there is good reason but it came to mind
 
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