Good afternoon,

I am needing to replace my TCU as I have some problems with shifting in Drive. I am trying to look for an TCU online by the same year, engine and transmission type but I get to a point where there are different TCUs for the same year, model, etc but with different part numbers.

Is there a way to find out the part number of my ecu using the VIN number as my TCU does not have any labels or anything(Im sure is not the stock one). My VIN number is 1J4FJ28S3SL565864.

 

Have you looked at your TCU? Does it have a number on it? What is the issue you are trying to resolve with a new computer?

 

No the TCU does not have any numbers on it.

The problem Im having is that whenever I put in D the revs will go up but the car will struggle so badly to move fwd as if you put a manual trans car in 4th gear and try to go fwd, whenever I put in 1-2 the car will just run fine but then after 1-2 I need to put it either on 3 or D as if it was a manual car.

I have taken it to a transmission shop, where they did kind of an overhaul thing to the transmission, but the problem is still the same, they tested the TPS and said there is nothing wrong with it. They have done quite a few tests and they came to the conclusion it has to be a problem with the ECU.

BTW trans fluid is ok, its using Dex/Merc III

 

Sounds to me like the Transmission Control Unit is where you should be looking. ECU has NOTHING to do with gear selection.

 

Sorry I ment TCU. Ive done a lot of reading about this and everybody says it might be either the TPS or some sort of cable that goes to the speedometer or something like that.

My guys at the transmission shop ran my car without the tcm connected and they were able to shift all gears manually. Im not really sure if that has something to do with the tps or if it means its good or bad. They said thay made tests to the TPS and it was ok. Not really sure what they tested thou.

It is so frustrating because so far I've spent nearly $1000 in stuff that haven't fixed the problem.

 

Can you shift the gears manually with the TCU installed also?

Go to www.cruiser54.com and complete Tip 10.

 

Yes, that's how ive been driving lately.

 

Do Tip 10. Then, remove the TCU and refresh it's connection with the plug. Note the color of the plug.

 

So I have finally received the TCU that I ordered off ebay and that totally fixed the issue. I spent a lot of money doing and overhaul to the transition for nothing

 

You are one of the very rare cases where it turned out to be a bad TCU, That transmission shop was utterly incompetent to have rebuild the tranny without verifying that the computer was working. The very first test is simply pulling the fuse for the TCU and seeing if you can shift manually.

 

Yes, that's what i thought, very incompetent people. But im happy now as I fixed the problem MYSELF.

BTW The TCU was connected but I was running it manualy with no issues other than shifting myself.