After fiddling with it some more it ran fine for a while then back to acting like a middle schooler. I took the loom connections apart and there was some white crud on the pins so I cleaned as good as I could reach and sprayed them liberaly. Drove OK.

Set off for a 500 mile trip and went fine for a while then started up again. I'd pull over and adjust the TPS and be good for a while then it'd start up again. The trip back was towing 8,000K so I wasn't going as fast but still same scenario.

I can't say it was the adjusting that seemed to temporarily make it go away as I also fiddled with the connections and wires out of desperation, frustration and to avoid emptying .40 hollow points into the TPS...

With the limited electronics our trucks have I'd go plum crazy with a newer truck!

 

KRB I have been reading all your posts hoping you found the solution. My 92 started this several years ago. At first I didn't know about this forum so I installed a new TPS and it did not help. It would not stay in OD for longer than 5 seconds at a time. I finally added a wire to the ground side of the OD solenoid on the tranny up thru the floor and peeled back a couple of inches of insulation and bent that end in a hook shape and every time I want it in OD I hang the wire over the gear shifter shaft which grounds the OD solenoid and it goes into OD and stays until I take the wire off the shifter as I am slowing down. I had done this for several years when I started reading this forum. Then I adjusted the TPS with a meter and...WOW it worked like a champ... but I was glad I didn't remove the wire I added because the next day or so... back to the in and out of OD only not as bad. Adjusted again and seemed to help again but I think it was just ready to work for a while. Some days it works pretty good and sometimes I have to hook my wire over shifter.
Mine worked the best for the longest after i took the circuit board out of the PCM to inspect it and looked for numbers and re-installed. I did that to order one from NAPA but they don't have any nor do they get any to rebuild so you have to send yours in and they will fix and send back. I am not convinced that is the problem but think it may the culprit. These rough riding Dodges may have done damage to the solder joints on the circuit board.
Keep posting. Maybe one day you or I will get enough time to get serious and figure it out.

 

That sounds similar to my problem, sorry to hear you're having to deal with a troublesome shift too.

I've yet to fiddle with the solenoid because I don't yet know what to check it for or how to measure. I'm not the best at electronics but I assume its just an open or closed circuit.

Never thought to ground it out to stay in OD but so far as long as I keep resting voltage low it will go into OD and mostly stay as long as my speed is maintained above 45mph or so.

Next I'll swap ECMs from my brother's truck to see if that affects it any. I've never thought to open one up but not sure what I could do once I did either. How long ago did you have your's rebuilt and what did that cost?

Thanks,

 

Haven't had it rebuilt yet. Can't do without the truck long enough. Through NAPA it is the same price for rebuilding yours as it is to buy a rebuilt one. I tried one from an online vendor and it wasn't like mine (the board looked different inside) but I tried it anyway and it wouldn't even charge the battery so I returned it. NAPA acts like they know the numbers of the replacement needs to match the numbers on yours.
The OD solenoid has 2 wires - one should have +12v any time the truck is running (maybe even with just the ignition on... not sure). The other wire is the -12v (Grd) but only receives this ground when all conditions are met and determined by the ECM. The conditions include ... Engine temp must be above a certain degree... speed sensor on rear of transmission must be sending the ECM the correct speed signal... TPS must be sending a correct range of voltage to the ECM... OD switch on dash must be off (light off if it is working). There is also one other condition but it is mechanical in the transmission - transmission must be in 3rd gear before it will send fluid to the OD. There may be one I have forgotten, this was off the top of my head. I can get the exact specs if you need them.

 

And the tranny fluid temp must be below like 280* or something.

I didn't realize the ECM was that involved. I'll swap and see what happens. Does NAPA rebuild just the circuit board inside or do you take them the whole thing?

It could have something to do with the temperatures it thinks its getting because it "seems" to me that in the cooler mornings the truck does fine but starts acting up later in the day or at the end of long drives (2-3 hrs). I didn't drive it much over the winter but I don't recall it misbehaving then either.

 

There is a sensor in the trans line near the shift linkage. You can try unplugging it and jumping the wires together on the harness. That will eliminate the temp sensor.

 

You are right and it is like 280* (273*). Mine also seems to do better when it is cooler but circuit boards can act up as they get hotter and expand (under hood temp). As they expand, a solder joint or trace can crack and cause erratic behavior.

You send in the case and all to NAPA. I am going to do that one day because my Cruise doesn't work and my headlights flicker at idle and Alt gauge jumps around until I get above an idle. The voltage regulator is also integrated into the ECM.

 

I spent years troubleshooting those danged flickering headlights. Added grounds, swapped ECM, added external regulator, etc. Finally one day notice the "green bloom" on the wiring loom. Dug into it and saw that a wire had corroded in two. Patched that and been good ever since.

I'll ask my NAPA about rebuilding the ECM. After 21 years it couldn't hurt any.

 

I'll check but I think I already by-passed that when I added my underbed cooler and used that port for the fan switch. Maybe should check that old modafication to make sure its still secure. Thanks,

 

j martin built a little resistor thing for me that basically bypasses the TPS and puts the shifts at a set point. Like a POT only not adjustable. Has worked like a charm since.

Have a couple hundred mixed driving miles. No hauling or over the road type stuff yet but at least the most annoying up & down stutter between 45-50 is GONE!

Thanks j martin!

 

Hadn't heard from you. Figured no news is good news.

It's OK for trouble shooting, or putzing around. If you're pulling something serious, ie more than a bass boat, I think it would be pretty hard on things.

It's not real bad, though. If you have the skinny pedal matted, it'll run up to 50 or so in second, then shift to third and OD in a quick 2 step.