Cruising down the highway all of a sudden tranny is hunting for gear, CE light on...

Ok, I was driving back from Hunt Camp last night. I had just driven 45 minutes of windy mountain roads and about 10 minutes of highway when I stopped to fill up the tank. Shortly after getting back on the highway the truck started to surge, lose power, surge, lose power, etc. The transmission was also hunting for gear, dropping down to 2nd, then up to 3rd, then down to 2nd, then up to 3rd(while doing about 65) sometime during this process the Check Engine light came on. Not knowing what else to do I pulled over. Sitting in the middle of BFE at 11:00pm on a Sunday, I figured I'd unhook the battery to reset the computer and see if it made a difference. Well, I unhooked it, waited 5 minutes, hooked it back up, got in and started it up. The CE light stayed off so I decided to push onward and see what happened. Well 200 miles later it hasn't happened again.

The only prognosis I could come up with was some bad gas, or the welding I did on the front axle bracketry on Saturday morning, had some delayed effect. Anyone come up with anything else? Thanks

Ary

Re: Cruising down the highway all of a sudden tranny is hunting for gear, CE light on...

Can you be a little more specific? Is this engine (power) related, or was it the tranny bucking/surging?

:huh:

Re: Cruising down the highway all of a sudden tranny is hunting for gear, CE light on...

I really am not sure. I think it was that the engine was surging and shifting into 3rd and then losing power and downshifting into 2nd to compensate, but I wouldn't swear to it.

Re: Cruising down the highway all of a sudden tranny is hunting for gear, CE light on...

could be a Jeep thing that you don't understand. my '98 does odd computer things a times, then resets never to be seen again.

Re: Cruising down the highway all of a sudden tranny is hunting for gear, CE light on...

Update

After leaving the dome light on all day while the Jeep was parked at the Metro Station, getting a jump, and driving home. I noticed that the Jeep was idleing very low in the 250-500rpm range and was varying a good bit in that range(i.e. it wasn't a steady low idle, it was jumping around). BTW, the weather changed from mild and dry to cold and wet, but it's never had that affect before. I had a 1/4 tank of gas left so I went and filled up at a BP/Amoco station. At first the idle problem appeared to have gone away, then came back briefly, then went away again. I'm crossing my fingers that this was all just the result of bad gas and nothing more. Any opinions on what else it could be?

Ary

Re: Cruising down the highway all of a sudden tranny is hunting for gear, CE light on...

EGR, unhook it and forget it. Psh I dunno.

Re: Cruising down the highway all of a sudden tranny is hunting for gear, CE light on...

ABout 5 months ago, my XJ did the same thing. I too had the same temporary solution. Long story short, replaced and adjusted teh TPS...no more problems.
BSD

Re: Cruising down the highway all of a sudden tranny is hunting for gear, CE light on...

WobblesXJ said:

EGR, unhook it and forget it. Psh I dunno.

Click to expand...

No EGR on a HO motor. Sorry, try again.

Re: Cruising down the highway all of a sudden tranny is hunting for gear, CE light on...

Everything still running smoothly, BTT for any last opinions before I let the thread die.

Ary

Re: Cruising down the highway all of a sudden tranny is hunting for gear, CE light on...

Argh, filled up the tank again on my way home from MD, and 10 minutes later the CE light came on. Maybe I should stop fueling up at Exxon. I will pull the codes tomorrow and report back.

Ary

Re: Cruising down the highway all of a sudden tranny is hunting for gear, CE light on...

Pulled the codes and it came up with a faulty TPS sensor. I went and picked up one at the dealer today since they won't be open tomorrow, but is there anything I can do to check the old one or check the system to make sure it is in fact a faulty sensor?

Ary