1989 Cherokee shifts funny.

[Canabalooza]

After spend some time up in the mountains with my girlfriend on the way back I noticed it was having problems shifting from first into second.
After getting back on the road I realized that when it shifts from first into second it looses almost all of its horsepower and I have to floor it to get it to actually shift again. If I start off the line and let it go really slow in second sometimes it makes a popping noise into third and then I get all my power back. If I floor it, it shifts up again and I get all my power back. Just in second gear that it looses all of its power. I checked all my fluids and I’m outa ideas. Any help would be great.

[Edbrooks]

One possibility is the TPS. Be sure it isn't loose. The Haynes and the Chilton manuals both show a process for adjusting it (as well as checking it.) Not as common, but it fooled five, yes, five area transmission shops (!) is the sensor in the distributor. I finally found that myself and installed a sensor. Returned transmission to normal. The pros had no idea.