Engine/Transmission (1998.5 - 2002) ECM problem? Marco, Bob Help!!

[tractorface]

My truck has had some strange symptoms over the past few months and I am beginning to think the ECM may be the culprit. Any help is appreciated. Here goes:

-Power, boost and smoke are down some days and fine most others. It does not change once the engine is started, if it is not right it will not "reset" until the truck shuts down and sometimes not for days. Could be the Raptor and Edge has offered to try and diagnose if I send it in. (very nice offer)

-Check engine light comes on and my Harrison R&D reader says no codes set and only communicates with truck for a few seconds then goes yellow or red. Takes 6 or 7 tries to even get it to "connect" at all. Tool works fine on wifes Subaru and Dad's van, as well as two cars at ,so I think it is fine. Also when it does "connect" to the Cummins it does not allow me to check off any options and acts like it is seeing nothing. Tough to explain in quick thread if you are not familar with the R&D package but suffice to say the package is not communicating correctly with the ECM. Once I get it to go green (connect) it says no codes set and MIL is off even though it is on. Now just after that I can restart the truck with no codes Like it cleared the MIL even though I could not choose that option

Truck runs great otherwise. I just don't want to get stuck. Do I need a new ECM?? What gives. Not sure if my two problems are connected but I suspect they are. I plan to get Someone else to try and read the codes but I am guessing they will have similar trouble. HELP

 

[Marco]

I don't know the tool you're using to connect to the ECM, so I can't tell you about it. Hey, yes, I've seen my share of ECM's with strange intermittent problems. So yes it could be that your ECM has a problem.



I would first of all try to get to a dealer and hook up a DRBIII to your truck in order to find out if it's the ECM or your tool that has problems. I mean, if the ECM has a problem then it should act the same with the DRBIII as it does with your tool.



If you should need a new ECM, Bob is most likely your best bet. He finds a lot of good used ECM's.



Let me know if I can help you further!



Marco

 

[tractorface]

Thanks, That is what I'll do. Maybe I'm just lookin for an excuse to get one of your "warmed" up ECM's... ... ... Who knows :-laf

 

[RHARVEY]

Have you checked you map sensor?????



Rick

 

[tractorface]

What makes you ask that? I have suspected the map sensor to be a problem for a while now. How could it affect the communication with the ECM? Anyway to "bench" test it? If I knew what type of signal it sent out I could check it with my multimieter. I have a 5v supply on my desk just need more info on the MAP to test it.

Thanks