Sounds like a ECM problem. I would start by cleaning All the grounds on the truck. there are two on the fender on the driver side..one near the bumper braket and another on behind the starter that you can get to if you drop the factory fuel filter housing out the way which is easier than pulling the starter off. That ground is the one directly related to the ECM itself , ground to the block. Your block is grounded of the battery. So ya they all go hand in hand. See if that fixes the fuel pump priming problem. Your ECM is the ONLY source of sign to make the lift pump run. Yes it has a power relay, but that relay gets its signal to power on from the ECM. I just replaced my ECM from the same intermitting problem.

You can remove the fuel filter housing to get the the ground near the starter, that will give you better room to get to the 50 pin connector on ECM and remove it with the truck key off. No you do not have to disconnect the batterys, and clean it with some eletrical cleaner. Inspest it for dampness.

You notice any other problems as in the WTS light?

 

there are no codes while using my scanner or anyother wierd symptoms just the no start deal

another question since it is an 01 I should be able to read the pcm codes from the odometer correct? b/c i havent been able too since all this started

any idea how to test if the ecm is bad besides swaping it out

 

I think that you should be able to do the key on off on that year. Thats possibly an ECM problem too. There isnt going to be any codes for no signal being apply to the Fuel lift pump. Its mostly run or no run.

 

crap well i guess im going to get back at it tomorrow and clean all the grounds then go from there...

any idea on where the good deals are on ecm's haha

 

could of wiring the map sensor plugs in wrong killed it or what?

 

Aah.. Map sensor is for the ecm to compute the fuel based on boost. It would run bad, It will start even with the map sensor unplugged, i have tried that before..I got mine used from the classified section here.

 

would it of killed it though

 

one thing to try not really sure but to 100% take the relay out of question because i had my truvk throwing a loos of communication with ecm and injection pump code ran thru it noumrous time thought my old comp shorted and nope still ahppend and one day a friend of mine and i were looking at it when it wasn't acting up and i set a beer can on top of the replay center under the hood and figured out the ASD relay actull had a bad internal connection. so you can swap the ASD relay and the A/C replay and try

 

ive replaced the relay already still a no go

 

Try and wire direct around the ECM and see if it cranks that would be my first go... Make sure every cylinder is getting fuel


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Try and wire direct around the ECM and see if it cranks that would be my first go... Make sure every cylinder is getting fuel

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i guess your talking about hot wiring the pump?

 

I would not think so, The Map sensor is a variable resister not very much voltage going thru there. Try hot wiring the Fuel pump and have it to run before you try to start the truck for a few seconds to see if it is a priming issue. and then see if the pump stay running on it on.

 

the only thing i can think of that would of killed it was if i got the + and the ground mixed up on the map sensor adapters

i guess if the grounds dont solve my issue ill hot wire the pump just to make sure..

im pretty sure its not the pump though, its been fed by an airdog since day one and i drove it today with no issues until i went to install that comp box

 

yes hotwiring the Liftpump. Its fairly smiple...Key on is the input signal to the ECM to run the pump, Output from the Ecm to the Lift pump.

 

i understand that... the lift pump will run but the truck still will not start like the pcm/ecm is not allowing the injection pump to fire off.... thats the issue sorry for any confusion

 

Just make sure each cylinder is getting fuel bottom line if it is it should crank


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i get that the issues stem from the fact that the injection pump wont send fuel to the injectors due to some wiring issue the injection pump itself is fine i just need to figure out if its a wiring issue or the pcm/ecm has failed... the symptoms are the liftpump will run but after a 3 to 4 second delay after the key is on, while it runs its clicks on and off at will...

 

Ok now...i have a lil better picture here...Crack open two or three lines at the head. 3/4 wrench, if it squirts likes hell thats good..if its a lil dripple or a small spit...or nothing..VP is dead. When my vp died it would pop, about as much pressure as a i could spit thru the line coming out.

 

vp death with no codes or drivability issues?

why would it do this before and keep on doing it on and off and then finally kill over now?

i guess ill hotwire the pump tomorrow and make sure its not the I/P

im still not sold on the fact that the asd relay wont click over, and im willing to bet thats the sourse of my problems but i have no way to diagnose that other than changing the ecm or chase down wiring issues

 

When I got my truck(has stick intank pump and lift pump) the in tank pump had no fire going to it.... If you could ever prime the system it would crank but wouldn't accelerate with out dying... That is why I say hot wire that relay is junk... The hole dodge wiring harness is junk I make my own for my power units and by the time I'm through with this truck it will be all mechanical.... Wiring is the devils right hand man


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new issue has come up i have no dash lights anymore...is this leaning towards a pcm or an ecm

 

I believe you have unintentionally discovered your problem... Or it's a weird coincidence


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alright yall ive narrowed down to the ecm, the cel light, wts light, abs light, and fuel light were flasing on and off at will, the lift pump would run every few seconds and my scanner would not pull codes while this was going on...

could i just have the ecm reflashed or do I need to replace it

 

little update... the truck is now running... I took the ecm down to cummins southern plains to be tested, it checked out fine so we took it back to the house, installed it and the truck now all of a sudden fired up..

did some more poking around and have come to find out that there is a short somewhere in the harness inside the cab that caused my issue....

the dash lights will come on and off randomly when i wiggle the harness under the dash next to the firewall plug

going to take a day off tomorrow and dive into the wiring to find the short

thanks for the help yall

 

UPDATE****

truck fixed read edit top of post