Tjwolf92

My buddy has a 97 xj that we've been trying to figure out for a good while now.
97, 4X4 NP231, 35/30, auto
Has "supposedly" had engine, trans, and t case swapped by PO

Ran fine for awhile, (couple months) off road only because it wasn't tagged. Then one day the RPM's skyrocked right after start up, was also having hard start problems. The RPM's wouldn't drop until you shut in off. (No tach so I don't know exact RPM's, but between 2-3K) removed TB, and cleaned it good along with the IAC and reassembled. What do you know, it's fixed! NOT, still has long start time, good cranking just takes a minute. Idles fine until it warms up. Once it gets to operating temp RPM's are back up, it'll pull you up slight hills in drive (still between 2-3k) Thinking it had something to do with the temp, replaced the CTS with one from AutoJunk and still doing the same thing. Could TPS cause this? only at operating temp? any ideas? Any advice helps, i'm new to any XJ newer than 92! Thanks in advance!

Tjwolf92

no codes either by the way, TB gasket is good, no major visible vacuum leaks. Haven't done the carb cleaner test since it only does it at operating temp.