'02 Sport XLS - Running hot?
 

Hi all,

Considering buying an '02 Montero Sport XLS, 3.5L 2WD and it seems like it runs a bit hot. It not overheating that I can tell but the guage runs a bit high (just about 3/4) and when I read from the OBDII it seems hover between 220 and 225. Engine fan seems to be spinning and I get same temp w/ and w/o AC on. It's pretty steady in that range whether driving or idling (didn't drive far, was a quick city-streets test drive w/ a private seller).

So on the surface it seems "normal" but I'm not used to seeing a car run in the 220's as a normal op temp. I checked around a bit and it looks like the thermostat on this car should be a 180 so all the more reason this seems high to me.

Can anyone confirm for me or point to an info source of what the running temps for this truck and engine should be?

Any thoughts on why it may be running high (if you agree it's high) but yet apparently steady at this temp?

Thanks much from a Mitsu newbie.

No first had experience here. There are threads out there where the temp gage has a problem on the circuit board giving false indication. Below is one such thread for repair of circuit board.

How to fix the faulty temp gauge on a Pajero/Shogun/Montero NM (2001-1003) | Pajero.guru

Thanks for the reply Larry. I've seen a few threads about the gauge problems but I'm pretty sure (almost positive) this is not a gauge issue and here's why:

The gauge rides steady around the 3/4 mark. It did not suddenly jump up nor down and it never reached the red. When the car was cold the gauge showed cold and as the car warmed up the gauge rose to the 3/4 area and stayed there.

Also, as I said above, I took readings from the OBDII system which is reporting from the car's computer NOT from the gauge.
It's from the computer that I got such exact readings to tell you that it runs between 220 degrees to about 225. The computer does not depend on the gauge or even the gauge's temperature sender. It has it's own sensor separate from that.

The fact that the computer reports 220 degrees and the gauge is steady around 3/4 makes me pretty certain that there is no malfunction. I would expect that 220 SHOULD BE around 3/4 of the way up the gauge.

The question is if that's NORMAL for this truck or NOT?

Thanks,
J.

I don't have a sport, but I have the same 3.5 in a 98 full-size. The temp from my ecu is usually at 200 +- a few degrees and the needle is right below half.

I don't think the car you are looking at is operating at normal temps. Maybe a stuck or incorrectly installed thermostat or none at all?

Thank you. That was my impression as well. Digging around I saw that the thermostat should start opening around 180 or 190 and should be fully open by 212 (100celsius). That makes sense then that you're seeing +/- 200 from the ECU and was one more reason I felt that 220 is on the high side and it's good to hear what you're running at. I'd like to hear from others as well, just to get a bigger "sample size" but I suspect most will be around the mid-gauge / 200 mark.

What puzzles me is how steady this one is around the 220-225 temp. A stuck t-stat could be one explanation I suppose and that would be an easy enough fix but I wonder if it might be more. Giving some gas to hold a bit higher revs (2000 rpm for example, which should increase circulation) doesn't seem to drop the temp, not even temporarily, so I worry it could be something more serious. Hopefully someone here may have some insight because I'm not sure what that might be. It looks to have a new radiator in it so I'd have to think that's not it. I'm open to any thoughts on what else to look at.

Either way your input is helpful. Thank you for it.

I bet the owner tried replacing the radiator to fix the issue or may have overheated at some point. If you're really interested, hope it's just something simple like the radiator cap.