ok so my jeep(01 xj sport, 4.0, aw4) just started doing this yesterday. and did it to me today twice.

so I got in the jeep started driving, got to around 55mph, and the torque converter unlocked and wouldnt lock back up. so I pulled into a parking lot and shut it off. started back up, and worked fine.

then this morning, same thing.

this afternoon I got off work, same thing, got to around 50-55 mph and it unlocked and would not lock back up. Again I pulled into the same parking lot, shut it off and tried to start and nothing...wouldnt start. pushed the shifter forward and bam started up and again the torque converter worked as it should.

so when I got home, I put it in park, shut it off, and tried restarting it. nothing again. pushed forward bam fired right up.

wont start in nuetral either.

I am assuming my NSS switch is out of adjustment which is the reason its not wanting to start in park, or neutral. I havent had a chance to see if I got reverse light.

Now I did the NSS clean up and reinstall last october. because I had no reverse lights.

But I am not sure if the NSS is playing a role in the torque converter lock up or not. will an unproperly adjusted NSS cause havoc on a TC?

 

just went to a buddies house and checked for any codes..

I had the following.

P0705-transmisiion range circut (prnd) which is the NSS I am assuming...

but still curious if a failing or faulty NSS will cause havoc on Torque converter lock up or not...

 

You have a code, which is ALWAYS a good starting point in trouble shouting. Since you cleaned it (some months ago) I'd just replace it with quality new one. Erase the code aftet this.
It will most likely solve the starting issue, see then what remains of the torque converter lock-up issue and take it from there.

 

I aint gunna mess with it till this weekend. But im honestly mainly curious about 2 things.

Is the torque converter affected by a faulty nss?

And is the shifter circut ineed the nss?

I have no qualms against replacing it. But I just want to know if I need to dig deeper into my lockup situation. I drive highway daily and cruising at 3 to 3500 rpms is just not ideal...

 

In! Been dealing with a similar issue.

 

I believe in later years like yours it does.

 

I'd think more the OD solenoid than an NSS causing this.