Novak Conversions Jeep Wrangler TJ radiator
@Wranglerfix could the problem with this be the skim of the donor computers?

No, the SKIM not being correctly paired to a swapped in PCM would result in starting and dying before you get it out of park and there would be a light on the dash showing that to be the issue. Unless you are misinterpreting it dying within 3 seconds or so as stalling under load. Are you?
 
I have a degree in physics and a minor in chemistry and I'm still amazed that they can design a fluid to act in certain ways like this.

The development of ATF+4 is pretty interesting if you can find the story about it. They were having a lot of transmission issues in front wheel drive mini-vans and needed a solution to solve a host of problems. ATF+4 is stupidly high quality and almost fully synthetic to get it done.
 
No, the SKIM not being correctly paired to a swapped in PCM would result in starting and dying before you get it out of park and there would be a light on the dash showing that to be the issue. Unless you are misinterpreting it dying within 3 seconds or so as stalling under load. Are you?

Using donor computer (99TJ 4.0 auto) it starts and stalls within a few seconds. Put original computer (99TJ 4.0 manual) it cranks and runs fine. Not worried right now about shifting.
 
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Using donor computer (99TJ 4.0 auto) it starts and stalls within a few seconds. Put original computer (99TJ 4.0 manual) it cranks and runs fine. Not worried right now about shifting.

Is the dash light on when it does that key symbol with a circle and slash through it?
 
Using donor computer (99TJ 4.0 auto) it starts and stalls within a few seconds. Put original computer (99TJ 4.0 manual) it cranks and runs fine. Not worried right now about shifting.

It sounds like the 99 auto has skim enabled. Do you known if the key was grey? I can program the 99 manual to auto if you send it into us.
 
It sounds like the 99 auto has skim enabled. Do you known if the key was grey? I can program the 99 manual to auto if you send it into us.

That was my next question to you if you could do that. Awesome. I will send it. I have looked up the site and think I found the area for this. Can you post the link so I can pay you and get the shipping address or if you can message me directly. I can’t yet since I’m new here
 
The development of ATF+4 is pretty interesting if you can find the story about it. They were having a lot of transmission issues in front wheel drive mini-vans and needed a solution to solve a host of problems. ATF+4 is stupidly high quality and almost fully synthetic to get it done.

You had commented on this before on another forum and a few years ago, I went and found a copy of that SAE paper (though my school contacts) you are referring to. Here is the link on the SAE website - https://www.sae.org/publications/technical-papers/content/982674/

It's a really freaking good read. The information is not difficult to digest at high level either. I have attached it here for anyone that is curious and I am going to tag @Mike_H given his interest in stuff like this.

Cliff notes for folks that want a summary without wanting to read the paper - https://bobistheoilguy.com/forums/threads/atf-4-rant-on-allpar.110206/
 

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So, It was the computer after all...and maybe some me. Sent the computer to be flashed with the automatic transmission and it all works great now. I was seeing it as a stall with the 2 new computers I tried, but I guess both of them had the skim still on them whereas mine didn't. Thanks to @Wranglerfix for the extremely quick turnaround on the computer! Also making sure the trans fluid is full helps too. Didn't realize if it's low it does absolutely nothing.
 
Novak Conversions Jeep Wrangler TJ radiator