I just got a 89 Cherokee automatic and I washed under the hood of it and now it won't shift out of 1st gear. I've been checking plugs, wires, fuses and tried doing different things and nothing yet. It sounds like something simple to fix. If anyone has had this same problem could you please reply. Thanks Corey

 

If it was shifting before, just let it dry overnight and it should be fine. What did you do to wash it??? Used high pressure???

 

Now it needs a lot of compressed air...........to blow it dry.

 

I just used a water hose to clean under the hood and thats been 5 days ago and it's still not shifting right

 

I would check the white and black connections at the back of the head by the trans dipstick. These seem like the only connection that would cause this kinda trouble.

 

I'll check those connections and see if that's the problem

 

Could the tps have something to do with. Because in a book that I have said that if it don't have the right voltage then it could cause the same problem. I just wish I could hurry up and find the problem and fix it, I have other things I won't to do it.

 

I seem to remember someone posting a comment about their TPS getting wet and crapping out from rain into hood vents, or a bad seal between the hood and the back of the firewall (I don't know what else to call it). As for whether or not it would affect shifting, I can't help you there.

Edited to add...

A quick search with Google yields this:

https://www.cherokeeforum.com/f2/93-...-sudden-23006/

https://www.cherokeeforum.com/f2/wha...-engine-16966/

 

The jeep runs fine and it shifted fine until I washed under the hood. Now when you take off I don't shift it just builds up higher rpms.

 

. u more than likley would be gettin a check engine light if a sensor or some type of plug was bad due to gettin sprayed directly.. but thats my opinion. i wouldnt think ur throttle pressure would have anything to do with it if it was shifting fine before.

 

Its a 1989, the check engine light automatically comes on after you drive a certain number of miles and had nothing to do with any of the sensors of plugs. Basically with this year there are no error codes and a worthless check engine light. Gotta find problems the old fashioned way.

 

Surely someone has had this same problem before and could tell me what the deal is. It just don't make any since. i just checked everything that could check on the jeep and even drove it down the road and it still won't shift out of 1st.

 

i unpluged the tcu and i could manual shift it prefect and when u put it in drive it would start in a high gear but would take off. so i guess the tcu is the problem i hope, but now the parts stores don't carry one.

 

hey man i have a 1990 xj did the exact same thing, its your throttl position sensor! i got mine from the junk yard for 17 bucks now it shifts like new!