I'm thinking I'll take it to a trans shop just for diagnosis and see what they say.

Like I said the only code I found was for a downstream o2 sensor... I saw on a jeep forum that my exact same problem was caused by this o2 sensor... I dont wanna be throwing parts at it but what are the chances its my culprit? To me it seems highly unlikely as I don't understand the logic behind it.

Would driving with it unplugged for a little while tell me if its my problem?

Here is the link to that jeep forum:
http://www.jeepsunlimited.com/forums...r-at-stop-only

 

First, mine isn't the same generation, so it's only based on my experience with my 96.

With that particular relay missing, the trannie doesn't communicate with the PCM, there's a power problem with the sensors and solenoids (no workie,) and I completely lost my 1st gear and overdrive & the transmission wouldn't kick down--I replaced the trans. solenoids and sensors and it had no effect on the problem. Replacing the relay solved the problem.

My thinking is that in his encounter with the mud, he may have gotten water inside that part of the engine bay and the relay may be corroded.

 

Before you take it to a trannie shop, try the relay thing. It doesn't cost anything to try and might save you some cash.

I don't think the O2 sensor has anything to do with your transmission not working right, btw.

 

Thanks Brian,

Ill definitely try the relay thing. Can't hurt.

I didn't think the o2 sensor would be the problem either, but since 2 other people said it was the culprit I thought Id check.

 

Brian,

I checked the relays and there was no Cooling Fan relay... There was an Rad Fan relay but it is a different type of relay so I couldn't swap them

After reading your latest response did you mean for me to remove a relay completely and test the transmission? Your first and second posts confuse me a little.

Thanks

 

On mine, they are interchangeable. I swapped in a known good one (a/c) and the transmission started to work properly. Probably on your's they changed the lineup (and what controls what as well?)

It was worth a look, sorry if it didn't work out.

 

NP Brian, I appreciate all the help I can get.

Then only other relay that is the same as the rad fan is the engine relay.

 

Try swapping them, if the engine won't start, you've found a bad relay.

Again, not sure that the problem would carry over from the 96, but otoh, it's a free try & you can always switch it back.

On my truck, 96 4wd, 5.2, & automatic (46re) it was just amazing. Fuel mileage & performance had been in the terlet & no it has power & economy that was missing before. Amazing what 1st gear can do.

Back to diagnostics, some questions. You're starting out in 2nd gear right? Do you have overdrive (does the overdrive off lite come on?) When you floor it, does the kickdown work--does it downshift into a passing gear? Mine was throwing a bunch of pcm codes, but the check engine light wasn't on.

 

what brian said, is the manual kickdown shift working? Is it downshifting at all or does it stay hung in third?

 

I'll give you a run down of exactly what happens:


I'll start the truck, throw it in Drive and I'll start in 1st.

As soon as it shifts to 2nd, then 3rd it will not downshift back to 1st regardless if I come to a quick stop, or a slow stop.

SOMETIMES when I come from a complete stop (id say 25% of the time) I will start again in 1st.

75% is definitely in second.

If I floor it, SOMETIMES it'll downshift after it bucks a few times... the MAJORITY of the time it will just rev up to 2500-3000 in the current gear and slowly pick up speed.

OD Light OFF light is NOT on, but manually turning it off doesn't feel like it does anything.

I have not been on any roads where the speed limit is high enough for me to go to 4th (OD) gear... too worried about breaking down far from my house.

Ill have to check though.

Magnet,

Thanks for the vid I'll have a look!