alboy97xj

ok so im having problems with my 97 xj shifting down... it will start off in what seems to be third gear... but if i shift it down into 1-2 it will start off fine and i have to just manually shift it... but if i leave it over night it will be fine in the morning for about a mile then go back to crap... any ideas? i have new tps... new trans control box... thanks in advance...
Alan

BuckB91XJ

If you'ver already replaced the TPS, I'd say it is not getting the 12vdc that turns it on.

alboy97xj

ill check the voltage in the morning... its just weird how it will be fine for a mile or so then go to crap...

alboy97xj

so ive read other things which said that it may be the shift solenoids... cheap place to buy them?

Ben.Sykes

Hey Alboy...

I am having the exact same issue with my 98 XJ. What did the problem end up being?

excess650

His problem sounded like the one that I had. Mine started out intermittently and gradually worsened to the point that I always had to pull out in 1-2, and then upshift to 3rd. My fix was to replace S1 shift solenoid.

cruiser54

I wish I could find the post and I can't remember which forum, but someone had the same issue and it was a fuse in the fusebox under the hood not supplying power to the TCU.

bigred56k

I am having a similar problem with my 1996 XJ 4.0 with the AW4. This all started out a few weeks ago, I was at my mom’s house and had left the Jeep running while I went inside to grab something. 10 minutes later I came back outside to find my Jeep idling like ****. So the next day I went ahead and replaced plugs, wires, cap, rotor, and the fuel filter. During the process of replacing the plugs and wires I broke the heater control valve too. If this sounds like I am rambling on it is because I want to give a step by step of what I have replaced/done. Any way the rough idle was cured buy the little tune up. The next day I was on the way to work and the bottom just seem to fall out when I would get into the throttle. After doing some reading I went ahead and replaced the TPS. That really didn’t seem to improve anything. So during the next couple of days The CEL came on for the bank 1 O2 sensor. So that was a given to go and replace the O2 sensor. This seemed to cure the hesitation/lose of power during acceleration. I had also removed the catalytic convertor when I was under their replacing the O2 sensor. Now on to the new issue, I will be cursing on the highway on my way into work and all of the sudden the transmission will downshift out of OD then fall back into OD??? Yesterday when I got off the highway and came to the stop light, it seemed like the transmission was stuck in 3 or OD when I went to take off. After manually downshifting into 1-2 she took right off. So this leads me to testing the shift solenoids. Last night I unplugged the TCU and tested the solenoids. They all were reading around 13.4, which is in the 11-15 range. I am now stumped on what could be causing this issue…. Gas millage is **** and I really am getting sick of driving it in this condition. Could it be possible that I do have a faulty shift solenoid only when it gets warmed up??? I am looking for any input that one can provide. Thanks, Tony

bigred56k

BUMP BUMP

excess650

It could be that the S1 isn't happy when up to temp. When was the last time you changed your trans fluid? Proper kind and level?

bigred56k

Since I have owned the vehicle I haven't changed the fluid, Just topped it off here and there if it looks a little low on the dip stick.

bigred56k

This morning on the highway it seems like the tranny is kicking it out of the over drive lock out... 70 MPH at roughly 2100 RPM then all of the sudden bang it either is down shifting to 3rd or coming out of the lock up. (if that make any since to you) Speed stays the same RPM jump to like 2300-2500.

excess650

If it increased in revs from 2100-2300 or 2500, it was just coming out of lockup. Lockup can be inhibited by the brake pedal switch. If you continue to have problems with not downshifting to 2nd or 1st, or not selecting 1st when trying to pull out in D or 3, its likely the S1 going bad.

Adjust the kickdown cable attached to the throttle body shaft. Drain and refill your fluid with Dexron III/Mercon. The recommended trans fluid change interval is 30K miles. If its dark or smells bad (burnt) it should be changed regardless of mileage.

bigred56k

I will look into the brake pedal switch a little bit, The kick down cable has been adjusted and re-adjusted 5 million times. It sounds like I might just have to bite the bullet and replace the S1 solenoid then.. Would any of these issues relate to the NSS?

excess650

The NSS sometimes has been the cause of not going into OD or lockup, but it sounds more like the symptoms I had when my S1 was going bad.