Bad ECM???? I was driving the other day, and my fuel pressure whent from 14 psi to 0 instantly. No fading, or crazyness, just dropped out. I babied it home, and have replace the lift pump. When i bump the key, the pump does not run at all. I swapped the relays for the fuel system, bumped the key, and lp still doesn't run. I checked voltage at the relay, and get 12.5 volts. I check the voltage at the pump when a buddy bumps the key, and i get 0 volts. There are no codes or check engine light on. I s the ECM bad, or something else? I didn't see any fuses that were blown, i didn't think there were any other than the relay. Please help, as i am getting frushtrated with this truck lately. I also have a thread going in this section about needing ne lift pump with this problem going, but i thought i would repost as it seems to be a different issue. Thanks for the help, as i don't want to replace mor unnessesary parts. Truck is a 2002 HO 6 speed 4x4.

 

That sounds a lot like the issue I'm having, except my truck completely died when it did it. I'm looking in to a bad PCM as that was what I was told controls the lift pump. I'm curious to see what suggestions you get on this.

 

The ECM controls the fuel system. The PCM does not do anything with the fuel system (lift pump, injection pump.) I have a guy comming over to my house tomorrow morning with a super diagnostic computer that will hook up to the truck and he can basically control the ECM and tell whats working and whats not. This guy specializes in the computer end of vehicals, so we'll see. I in a way, hope it is the ECM, and not a broken wire somewhere. I would rather spend a few more dollars and replace the computer, than open up the wire harness looms and trace brittle touchy wires around.

 

Ok, established the ecm is bad. Now, i can find 2001 ecm's, but no 2002. Is the ecm the same, but just programmed differently? In other woeds, can i buy a 2001 unit, and have it reprogrammed by cummins for my spechs in an '02? I'm getting worried about beeing able to find one for my truck. Also does anyone know a good place to buy one if the 01 isn't interchangable?

 

Buy a Smarty and use it to reprogram the ECM. Will cost you the same as having the dealer reprogram it, plus you get to keep the Smarty and do all other things it can do.

 

Buying a smarty is in the future plan, but how does that fix the ecm if there is component failure like a chip or capacitor? Are there aftermarket ecms available? Or are they only for highly modified trucks?

 

Check with local parts yards on the ECM. I got one for a customer from a place in Connecticut through my parts yard I deal with. Only thing is the vin that is flashed into the module wont be the same.....

 

If i buy an ecm from an 01 that works so to speek, can i just go to the dealer to get it reflashed with my info, or do i half to send it somewhere? Acummind dealer told me that they would need the whole vehicle there. Does that sound right?

 

Still interested in this thread, found an 01 long block with the ecm cheaper'n I can get an ecm from the junk yard...

 

What I meant is, once you get a replacement ECM, get a Smarty to reflash it instead of paying the dealer to.
I understand that a Smarty will do all and more than a modified ECM used to do in the past.

 

Oh.. does the smarty have the stock program in it already, or does the ecm have to have the stock program in it for the smarty to save? A smarty is in the future plan, but this ecm, lift pump issue is going to set me back a bit, and i need to get the truck running as soon as i can. At this point, i am trying to avoid unessesary purchases. Budget is tight, even though the FASS lift pump is a much better pump than stock, it was a $275.00 purchase i didn't need to make at this point. My wife is getting with this truck "thing" and is at me about getting rid of it. So i have to carefully get this going for a while, till enough time passes, then i can slip in some upgrades here and there. Sorry PaulDaisy, i'm learning alot about this stuff in the last 3 days, kinda getting fried.

 

ok, there is a dodge part # for usable ecm's and it # 5083997aa this could be used in a 1998.5-2004. There is a technical service bullitin from dodge, that they were getting out of recieving pre programed ecm's from cummins, and they come unprogramed so dodge can load the apropriate one for the vehicle. Sooo if there are any ecm's with that part number on it, that should work for me if i can find someone to program it for me. There might be a r in front of the number for a reman ecm.

 

Smarty has a stock program in it so that you can return the truck to stock to make Smarty resellable or the truck stock. Some people bought or borrowed Smarties from friends just to reprogram ECMs to a newer stock code and get the new high idle.