Rocket

Hey everyone, have a possible issue with the Jeep and finally decided to join the forum having visited often.

Model: 1999 Jeep Cherokee XJ 4.0 I6

Issue: Well, since I've had the jeep(4 monthsish), I've always noticed the temp gauge acts differently than any other car I've owned. When I am driving down the highway, it'll peg in the middle of the second and third notch on the gauge; however, whenever I get off the highway and slow down, it slowly creeps up until I get the car moving at a good speed. Today it just seemed to climb a little faster to 210 and even slightly passed and didn't want to drop as easy as normal. I was never sure if this was normal as most indicators stay in one spot once the vehicle is heated.

Never overheated or gotten to the first notch past 210, fans kick on, no loss of coolant, bled the system about 2 months back when I replaced a radiator hose. Heats pretty weak so I'm not sure if that has anything to do with cooling system.. had the heater core flushed already. Might try replacing the thermostat.

Is this normal on Jeeps for the gauge to move around so much or could there be an issue? Thanks.

kidkodiak

my 1990 fluctuates a bit, my 2K1 doesn't at all, do with that what you will.

It should sit right around 210*.

Doesn't sound like anything significantly funky though. Curious if anyone else has an opinion.

EDIT: btw, if heat is pretty weak, try backflushing the heater core. You can blow a ton of junk out of it and get it blowing nice and hot again.

djb383

I'd suspect a bad fan clutch. Efan kicks on at 218F. Sounds like u r getting something like +/-40 degree temp swing and that seems a little toasty for this time of year. Sounds like u r gauge is wacked unless u r running no or very low temp t-stat. Always a good idea to verify temp to eliminate a false reading from the goofy gauge.

kidkodiak

I thought this too, actually, but I replaced the fan clutch in my 1990 last year and it still fluctuates like that, so my brain moved past it. The fan clutch is the most logical though.

LaredoBucket

My 92 would do the same. The radiator finllay sprung a leak, so i had it boiled and patched back up at a radiator shop for $45. It seemed to run a lot cooler afterwards.

LaredoBucket

woops double post, sorry guys...