JeepinCherokee

Hi there, new to the forum but need HELP! I have a 94 Jeep Cherokee 4.0 Automatic, It runs at 2g and overheats less than 5min, i just did an engine swap, new water pump, new radiator, new thermostat, new fan clutch. I checked for vacuum leaks and couldn't find any, it also has a hard time starting up and the last time i had it running the headers got so hot they turned orange.. so i let it cool and disconnected just after the headers because the headers are new so i knew that they weren't being clogged, started up again and seemed to not get AS hot but still hot, Questions, i checked and didnt find one but ppl keep telling me there might be a reverse flow water pump? Does the TPS need adjusting? and witch one is the TPS (3 or 4pin)? and Could IAC have something to do with it? i am desperate for help and appreciated any advice THANK YOU!!

dilljeepo

This seems dumb but... did you put in a new thermostat (the right way)? And does coolant actually flow through the pipes (your pump is working?)
As for high idle.. probably IAC try disconnecting it and manually changing the plunger a bit to see it the idle changes rpm at all
if it does and you can get it manually down to 6 or 700 then it's probably the IAC motor

DFlintstone

Lean, check fuel pressure? Swapped WHAT? Coolant's circulating/rad is getting hot too? Power brake with the cap off, check for bubbles. (HG will cause a fast overheat). Rear CCV tube has the proper orifice/restriction? I ask that because a guy just had a regular tube on a recent post, a giant hidden vacuum leak.

I'm pretty sure the pump and coolant all go the same way, in the northern hemisphere anyway!

JeepinCherokee

Thank you for the fast reply's, i have to use this forum more often, sorry for not getting back right away, i dont much time off work. OK so i found a big leak in the intake/exhaust gasket= replaced it and it idles down now... like normal idle. But it still has a hard time starting and when i get it started it still overheats.. just not as fast anymore, i checked the water pump and its pumpin.. the thermostat im almost positive is on correctly but im going to verify next time i get to work on it. OH and when i do have it running and i get it up to like 2g it kinda puts.. like "coughs"

RacerX

Sounds a little like mine - I'll have to check for gasket leak, and all the other non-coolant stuff ( I haven't changed that stuff in months).

Also Like to hear about your put-cough issue (mine does it getting on freeway)

fishtaconc

Copied this from tjwalker, it may not be the issue but, for the "cough", its worth a shot:

You should have 5 volts going into the TPS. At idle, TPS output voltage must be greater than 200 millivolts. At wide open throttle (WOT), TPS output voltage must be less than 4.8 volts.. The best is to use an analog meter (not digital) to see if the transition from idle to WOT is smooth with no dead spots. With your meter set for volts, put the black probe on a good ground like your negative battery terminal. With the key on, engine not running, test with the red probe of your meter (install a paper clip into the back of the plug of the TPS) to see which wire has the 5 volts. One of the other wires should show .26V (or so). The other wire will be the ground and should show no voltage. Move the throttle and look for smooth meter response up to the 4.49 at WOT.