krazykorean35

just replaced the thermo for a 195* cuz the car was running right above the 0 mark on the temp gauge, now it still only goes to the 160-185 mark even after idling for a while.

whats causing this? wrong thermo? bad coolant temp sensor?

(Eckks-Jay)

could be your heater control valve. has it been bypassed? does it still open/close?

krazykorean35

sorry ffor the noob question but where is it located in the engine bay?

(Eckks-Jay)

Above the oil filter kind of on the firewall.

krazykorean35

oh, and the heater works fine when the car is on, and both the upper and lower radiator hoses get hot when its at 160.

troy fritz

I have a 96 XJ and it runs around 210 all the time. I have alot of buddies with Jeeps and 210 to 215 is the norm.

krazykorean35

bump, still running at 160*

anyone know if a bad coolant temp sensor would cause the car to run colder?

5-90

A failed/failing CTS won't cause the engine to run cooler, but it will cause the gage to read wrong.

The CTS for the gage is at the driver's side rear corner of the cylinder head, outside the valve cover. BE VERY CAREFUL changing the thing - it's easy to break!

If you get it out, coat the threads on the new one with PTFE paste or never-seez (either will work) and install. Tighten with a wrench to about one and one-half flats past finger tight (it doesn't need to be crammed in, just tight enough to not leak. You're not holding more than 20psig in there.)

wwxjwheeler

If the electric fan sending unit is malfunctioning then it could turn the fan on prematurely and not let it reach operating temperature regardless of what your thermostat is doing. Is your electric cooling fan running alot or all the time? My fan does not kick on until 205 degrees.

Alternatively you could use an inferred thermometer and see if your engine temp and gauge temp are in fact the same.

xj_maniac_newb

now if you have had one installed like mine then it will give more exact temp readings mine in these colder days takes some 5-10 min to reach 210 so weather has something to do with it as well......kinda off topic but just wanted to put this out there, did you know that some xjs where made with a built in pre-crank engine warmer? if you dont believe me check ur manual lol thats where i found it

cherokeechief8891

i have an '88 w/ a 4.0 and i am overheating tremendously so i am in the process of switching out the closed cooling system by putting in a radiator out of a '91 that has a radiator cap but i was wondering about the tempture sending unit around the block... i know there is one in there some where and i just wanna know if there are two different sensors that controls the temp guage and if there is one that controls the coolant to travel through the block and passes through the radiator

john

kswiencki

on the older 4.0 there is... one about center on the drivers side and one in the thermostat housing... correct me someone, but im pretty sure that the one in the housing is for the gauge, and the other is for the pcm/fan....


as for your overheating issue, does it still peg the gauge with the new radiator??? do you get any heat? hows that water pump??? ive seen them look perfect, but the fins on the impellor rotted off.... (2000 XJ.. the guy boiled the head off of it cause of this...)

dudels99

my jeep did the same thing, took forever to warm up, temp was low, stayed at 180 for some reason. had a bad clutch fan, changed it out and all problems went away. runs 210 all day long, and warm up is way faster.

cherokeechief8891

not quiet yet need to get some brass fittings that will plug the oil cooler lines but before it didnt take in any of the coolant and the heater blew cold. changed the therm. and water pump... the old one had drag in bearing thought it would have solved it but failed. so i gotta finish up and see if the radiator is gonna fix it or not but if it still over heats check the fan clutch?

krazykorean35

the fan does just turn on as soon as the car turns on. i think thats it.

was ur fan acting like it was stuck on when you had a bad clutch fan? also it hard to replace etc?

thanks