Automatic Transmission Isn't Shifting

[britton]

Jeep TJ 2000 4 Banger

I'm going to list my symptoms and what I've replaced, let me know if you can suggest what might be the problem.
So I recently had a newly rebuilt engine put in and had basically everything inside replaced. So my guess is that it is a wiring issue instead of a gear/mechanical issue.

Symptoms:
Idle's perfectly
When accelerating and getting to about 2000-2500 RPM my gauge begins to bounce up and down, when trying to accelerate it stays in that range bouncing between 2300- 2500 RPM and the UP Shift light indicator flashes on when accelerating and turns off when decelerating.
The Jeep seems like it doesn't want to shift into a higher gear and hesitates in the same spot continuously until It starts going downhill to gain more momentum.

Please let me know if you find anything

 

[JP98]

Jeep TJ 2000 4 Banger

I'm going to list my symptoms and what I've replaced, let me know if you can suggest what might be the problem.
So I recently had a newly rebuilt engine put in and had basically everything inside replaced. So my guess is that it is a wiring issue instead of a gear/mechanical issue.

Symptoms:
Idle's perfectly
When accelerating and getting to about 2000-2500 RPM my gauge begins to bounce up and down, when trying to accelerate it stays in that range bouncing between 2300- 2500 RPM and the UP Shift light indicator flashes on when accelerating and turns off when decelerating.
The Jeep seems like it doesn't want to shift into a higher gear and hesitates in the same spot continuously until It starts going downhill to gain more momentum.

Please let me know if you find anything

How is the trans fluid level. To properly check. #1 Get the trans fluid warmed up. #2 Move the shifter from park into drive and then back to neutral. #3 leave Jeep running, in neutral and then check fluid level.

 

[Chris]

How is the trans fluid level. To properly check. #1 Get the trans fluid warmed up. #2 Move the shifter from park into drive and then back to neutral. #3 leave Jeep running, in neutral and then check fluid level.

X2 to this. So many people don't check the fluid the right way and that ends up being the culprit.

However, being as though you recently replaced the engine, there's also a very good chance you need to retrace your steps and figure out if you installed something incorrectly or forgot to plug something back in.