ok well the 90 xj was running hot so i have replaced the radiotor themostat(it didnt even have on when i bought it) hoses and water pump it will run ok you have to start it in low and shift it into driver and about 20 minutes it will loose power and start to back fire a little. any help?

 

the front end also kinda sinks down when you give it gas and we had to pull it home the other day i was not pushing the brake but one brake seemed to be on when i got i home it was smoking (just that one brake) i never
hit the brake

 

Sounds like a head gasket with a few Other problems...i.e. Neutral safety switch or somthing, or maybe the ecu for the trans is Fried, and possible a frozen caliper

 

Drive it like you stole it.

 

bad o2 sensor(s), sticking caliper

id guess o2's cause of the poping, backfire thing...

 

Could that be why it won't get over 2k rpms? Or pull right? Also if its in park it revs normal 3k or 4k rpms