Hi guys new to the forum, been learning a ton with you all.

Problem:
Cherokee XJ 93 transmission AW4 auto
-Initially did not shift gears unless I absolutely floored accelerator - code reading showed bad TPS - replaced that.
- while problem improved 90% still harsh shift first to second remains - almost not perceptible when oil cold, once it warms up jerk becomes super evident and is uncomfortable and annoying when driving around.

- adjusted TV cable, replaced shift solenoids, transmission oil, transmission filter, actual gears were inspected and look solid with about 65k miles on them.

Am I looking at a faulty TCM?
Any tips or ideas of what could be causing this jerky shifting only when shifting from first to second, and only when oil is up to running temp. ?

Help would be greatly appreciated, this is the kind of thing that drives you nuts and adds up slowly on the mechanic bill.

JV

 

CRUISER'S MOSTLY RENIX TIPS

TRANSMISSION CONNECTOR REFRESHING

OCTOBER 30, 2015 SALAD 29 COMMENTS EDIT



Over near the transmission dipstick tube are 2 rather large connectors. One is black and goes to the NSS and the gray connector goes to the transmission itself
. These 2 connectors carry all the info between TPS, TCU, NSS, speed sensor, and transmission solenoids.

Unplug each one, visually inspect for corrosion or bent pins, spray them out with electrical contact cleaner and plug them back in.

Additionally, if your Jeep is an ’87 to ’90 Renix, it’s always a good idea to reach up under the glovebox area and unplug the connector to the TCU and spray it out along with the receptacle of the TCU. While you’re there, find the fuse right in that area for the TCU. Remove it and spray out it’s receptacle and clean any corrosion from the fuse.

 

also, have you observed the TV cable moving/adjusting? It's not stuck in one spot, is it?

Which fluid did you use when you changed it?

 

Thank you, I’ll give this a try and give you feedback soon

 

- TV cable moving, doesn’t get stuck
- talked to mechanic they filled with ATF4 so it’s def a red flag to start with (Dexron III from what I hear is the way to go, would it really make one gear jerky and not the others?)

as for the the connection refreshing car is with electrician trying to get central locking to work, will def start there and see if there’s any improvement.

thanks again

 

That fluid being in there is a wild card. I would change it no matter what. A coupla drain and fills should do it. One gallon of dex/Merc needed per drain and fill.

 

How many miles would you drive between the drains and fills?

 

10.

 

Hello @cruiser54

So finally got to work on hitting them 2 connectors with contact cleaner. Did that + replaced the ATF4 with Dexron III (2 flushes), still no luck. First to second still rough as heck, other gears go in smooth as they can be.

List so far> adjusted TV cable, replaced shift solenoids, transmission oil DEXIII, transmission filter, actual gears were visually inspected and look solid with about 65k miles on them.

Thinking TCM next, but doubting if it will change anything
suggestions?

Thanks again

Codes
12
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41
55

 

Make sure the TV cable is adjusting and not stuck with a lot of tension on it.

 

I doubt it's the TCM. That just tells it when to shift. TV cable is what determines internal fluid pressure and hence firmness.

 

I was messing around with the cable this morning all seems ok.

Since the the harshness is viscosity related (as the trans oil gets warmer/ thinner the shift gets worse) I was wondering if putting a thicker oil like royal purple would make it a little less noticeable. Kind of like throwing a bandaid at the problem but still …



I

 

I wonder if the throttle valve itself is stuck or sticking based on how much slack there is in that cable.

 

Doubt it, I tried to upload a video but for some reason couldn’t. That’s me pulling the cable whilst holding throttle open. It’s got a good spring tension without feeling too tight.

 

As the fluid thins with heat, I would expect the pressures to drop a little and be less firm. Not more firm.