Greetings,

First, I'd like to say thanks to the all the folks here. I've recently acquired a '99 Ram 2500 4x4 with the 5.9L. I've already been able to fix a couple minor problems by searching the forums (faulty TPS and a bad OSS on the trans) myself at little cost. The knowledge available here is amazing.

I've encountered a new problem with my Ram, however. It used to start very reliably. Now, every so often, it won't start. It cranks easily, so the battery and starter are fine. I have been able to get the truck to started again by disconnecting the neg. battery terminal for 15 min or so, which I believe resets the ECM. Once started, the truck runs normally and can be restarted throughout the day, no problem. After a few days of sitting, it won't start again.

This seems like a computer problem. Can anyone confirm this? Is there some way to diagnose that it is the computer not doing something to allow the engine to start (injecting fuel or firing the spark plugs)? It may be related to rain, as the truck sits outside, and it seems like this most often (but maybe not always) happens after rain. The driver side floor mat also is damp after rain, so water is getting somewhere it shouldn't.

Anyway, is the ECM the black box with three (I think) electrical connectors on the pasenger side firewall?

Any help is appreciated and thanks in advance!

 

Yes that's the pcm on the passenger firewall. The water is most likely coming from the 3rd brake lite or around the rear window(3rd brake lite most common) . As far as starting issue goes, when it won't start you have to find out what it's not getting when it happens, spark or fuel. You could start by checking all the grounds, and make sure both battery cables are good. And all the connections to the sensors. Check all the fuses and relays to make sure they are not corroded. You could also disconnect the neg battery cable and turn the ign key to start for 30 seconds or so, then remove the plugs to the pcm and see that they are not corroded.

 

I have a 2000 dodge ram 1500 5.9L and it started killing the engine while I was driving ( quite dangerous I might add ) then it would not start and when i waited for a while it would start right up( the engine would turn over but it would not start like yours)
after a few times of being stranded in the middle of the intersections I noticed that my odometer read (NO BUS) and the engine light was on so during the process of elimination I figured that when i wiggled the 1st of the 3 plugs closest to the driver side on the power control module the (NOBUS) would go out and the engine light would go off then the truck would start right up and go until the next time it would die.

NOTE: DO NOT MESS WITH THE INER WORKINGS OF THE PLUG THEY ARE NOT REALLY TAMPER PROOF I KNOW i MESSED MINE UP GOOD! I have been looking at junk yards for the same plugs I think that it has to be the excat same year because I got one off a 99 jeep cherokee and the plug is right and the wire count is right ( 20) wires but I think that the pin are different than the holes on the plug so my search goes on.. I hope this helped at all and if you find out where to get a pcm plug kit please let me know thxs

 

the 3 pcm connectors are rebuildable.you can service them if theres a bad connection.just a FYI.