I have a 1998 Cherokee sport. Every thing runs fine while cold. In hot weather mostly after she heats up, when I come to a stop and then accelerate the transmission is slow getting into gear then it engages. If I roll to a stop and put it into first gear (low) she goes right into gear and other wise while driving she shifts with no problem.
When I bought the vehicle it was mid spring will mild temperatures and did not notice this at all until summer came and it got warm and hot out.
Any idea's?

 

Check fluid level and adjust the throttlebody to trans cable.

 

Very interesting because I just searched this on YouTube and 2 videos like this came up. I'm going to try this over the weekend. The only thing that bothers me is it seems to be temperature related plus in the video's they are not specific to what kind of shift problems they are referring to.
However it is a simple way to start.
Very much appreciated. I will keep you posted.

 

The cable controls the hydraulic pressure based on throttle input. Too loose can cause sluggish or no shifting at all, and too tight can cause harsh abrupt shifting.

 

What color is your trans fluid?

See my sig, #3.

 

I did check the transmission fluid when I first learned of the issue. The level and color seemed fine. I think that the person I bought it from may have been aware of the issue and may have had it changed. Not sure. Just assuming at this point. I just learned of the cable adjustment yesterday and will wait till this weekend to give it a try.
What grounds should I take apart that could be troublesome? I am an electronic tech and when it comes to grounds I do not check and eye ball them, I take them apart and clean them. I have a 95 XJ and never had issues like this but see that the wiring and electronics is an entirely different scenario between the two vehicles.