cody98

When i jump on the freeway on a slightly cold morning in so. cal it jumps in and out of overdrive and then will proceed to down shift into 3rd gear. Now if i were to drive the truck around on the side streets till the trans gauge starts to warm up it usually doesnt do it. I have put 3 new overdrive solenoid in it. The trans is under warranty and he seems to think that my rebuild ECM is burning up parts.

I have had this problem for quite some time but depending on how warm or cold the outside temp. determines weather or not it does it. and i just got the trans rebuilt about 1 1/2 years ago with 30 thousand miles on it. And it only does it going to work in the morning after the truck has sat all night, on the way home i can drive it as fast as i want and it never jumps out of overdrive or 3rd.

i know my TPS is fine. Have had it hooked up to a computer when driving and the volts do not jump and are at the recommened voltage.

Does anybody and ideas??? or maybe a place where i can get a used ecm that i know is in working order in the so cal area?

.

j-fox

Let me say welcome to a new member!
Now, the issue your truck has is an electrical noise. Clean all grounds. do a search on it and learn what is going on.

What year is the truck?

cody98

already done. Electrical noise doesnt exist on the 12 valves thats the 24 valves. bought the noise muffler deal that you put between the alt. and ground. Spent all that money cause that is what my trans guy thought it was to but non of it worked


Its a 1998 12 valve

patdaly

Cody, check the voltage at the trans connector. Also, make sure the connector is good, the PCM only drags the TCC and OD to ground, so it is kind of counter intuitive.
You should have a good 12V on pin 1, TCC Ground is Pin 7, which goes to B11 on the PCM. OD Ground is Pin 6 to B21 on the PCM.

Make sure your tranny guy understands these solenoids are being drug to ground to operate.............I am not sure just how a PCM could burn them up.

cody98

Yea i will write that down and take it to him. He is a a small shop that everybody likes around here and has been good but he pretty much has given up on my trans and is in denial that its the trans or any parts inside.

So what your saying is that the ground is screwed up rather then the parts going out. I mean every time he puts a new solenoid in it works great for some time then eventually starts screwing up again. Maybe vibration after time is loosening them up??

Also i did notice this morning that my speedometer was making erratic pegs to 120 and then going back down did it about 3 times then never again. This is the first time i have ever seen it.

Another thing why does it only do it first thing in the morning when its cold and sits over night?

patdaly

Check out the plug that plugs into the trans........... They sell them aftermarket. Perhaps it is not plugging in securely, or the 12volt pin is not engaging all the way, takes some heat to make contact? I know this, the next time it screwed up, I would have a manual switch to drag it to ground to test the solenoid versus just replacing it.

How are the solenoids failing? ( coil burnt or solenoid stuck )

cody98

ok i will take a look at that. I dont know why they went out or what exactly happened all i know is that he has replaced them. I cant get much information from the guy i took the trans to him when it started and he said that i had to re-due the whole thing. He never fixed it and hes pretty much given up. I got dooped. I will take a look at the plug.

I'am assuming its on the drivers side?? And how do i make this manual switch?

13FOX

I have this exact same issue. I've replaced all parts to include 3xTPS which still burned out. I even put in a new PCM. The problem is inthe wiring harness. Trust me on this one. Also the 12v does have noise! I'm at the point where I have ordered new plugs for TPS and trans. The wiring harness will be pulled out and all trans related wiring will put separated from the main engine harness and new wires will be ran, then covered with eletrical sheathing which can be bought at car stereo shop. This is the last step before I have to buy a wiring harness. dodge wants $1500 bucks so I gonna try the cheaper route first. Just thought I would share what I'm currently going through.

Daniel

cody98

Fun thing. After all the money and everything i took off the connector that goes to the solenoid in the trans ( it was pretty gunky and wet) cleaned it up and then stuck a small pick and squeezed the contacts and drove it to work this morning with no problem at all.

see i had a electrical shop go through everything and there was no problems with any of my wiring.

Hopefully my fix was as simple as that

rebal

check the plug at the trans they are known to get exposed wires from oil shrinking back the insulation . also the trans relay could be acting up

j-fox

Try this.

Find the big wire that runs from the alternator area to under the pass. battery and wrap it with aluminum foil.

Pennies and a few seconds will confirm the electrical noise!

patdaly

Funny how that works, lets hope it was just an intermittent connection, keep us informed!

13FOX

Went through the wiring harness this weekend. I found corosion in quite a few pins and connectors. actually had to pull a pin out of the C1 and C2 connectors and redo it with new wire. Got the TPS wired in. Also had some burn wires as well. I had stripped back about 8 inches of one wire before I found some clean copper. And Cody98 you're right about that 8 pin plug. I was full of junk and I've got a new one waiting at the parts house.