Sick Jeep - Suggestions?

I just had to go through the mud hole at Hollister today even though it looked pretty nasty. Well it was. It was part snot, part quicksand and part water.

My engine compartment looks pretty clean and the engine seems to be running pretty smooth. 1995 I6 with automatic.

When I put the trans in "1-2" it seems to be OK.
When I put the trans in "3" it stays in third gear no matter what. It starts from a complete stop in third and just stays that way.
When I put the shifter in "D", it stays in third and does not shift into overdrive. It also stays in third no matter what.
I got HORRIBLE gas mileage on the way home, possibly from being in third instead of overdrive but it seemed worse even than that would cause.

There is no water in the trans.
There is no water in the engine oil.
Reverse works fine.
The trans controller under the dash never got wet at all.
My charging system and battery are doing fine.
I do need to change my starter, I carry a spare for just such occasions.

I have not checked the diffs and transfer case for water yet. I will but I doubt that has anything to do with the shifting issue.

I am certainly going to change all fluids before I drive it any further.

What is the likely cause of the shifting problem and very poor mileage?

Thanks in advance.
Dan

maybe the tps or turbine sensor got wed and shored out....

There is a selector switch on the right side of the transmission. If it got water in it, or mud, it will tell the TCM all sorts of conflicting information and your shifts will be erratic. Just a thought.

Please disregard; wrong thread.

My Jeep acted the same way a few years back and it turned out to be a short in the transmission wiring harness.

Thanks for the suggestions so far.

I'm not going to get a chance to clean it up and really look at it until this weekend.

Any other suggetions would be helpful.

Thanks again.

Hell man. From what I've seen around here the TPS is a big problem.

Unplug the TCM and drive it manually shifting. If it drives Ok, concentrate on electrical issues as the transmission is mechanically Ok, including the fluid.

maybe your solenoids are bad too.......

joe_peters said:

Unplug the TCM and drive it manually shifting. If it drives Ok, concentrate on electrical issues as the transmission is mechanically Ok, including the fluid.

Click to expand...

X2. I did that for several weeks at one time. Highway mileage sucks.

I think you have an electrical problem or lack of electric into the transmission.

I finally got a chance to clean up the rig yesterday. After I hosed all the mud off the undercarriage and let it dry, the trans shift just like it is supposed to. Unfortunately, I'm still not exactly sure what was really wrong but it runs fine now. I guess it was a little too much moisture causing an electrical connection to short or not make a good connection.

I will keep a close eye on it and see how it goes.

Thanks everyone for the suggestions.