Still getting hot

[ranchand58]

2000 XJ, replaced water pump, thermostat, cooling temp sensor, radiator, coolant, thermal fan clutch, and electric fan. Temp stayed about 210 after replacements. Electric fan does not come on at all, even when ac is turned on. Any ideas? All suggestions welcome.:confused:

[prerunner1982]

If the electric fan still isn't kicking on I would check any associated fuses/relays. If the fan is getting power I would look at putting in a manual on/off switch for the fan. Just have to be mindful of the temp and remember to flip the switch when needed, especially see as you have a year that is known for cracking the head.

[Carves]

I think they changed the fan activation on the 2000/2001 models ?

Fairly sure its only activated by the coolant temp at 218* and not the A/C as well.

An over-ride switch for the fan, as prerunner1982 mentioned, is not a bad idea.

[Mudderoy]

I think they changed the fan activation on the 2000/2001 models ?

Fairly sure its only activated by the coolant temp at 218* and not the A/C as well.

An over-ride switch for the fan, as prerunner1982 mentioned, is not a bad idea.

Friend at work with a 2000 XJ claims the electric fan doesn't come on with the A/C as well.

[Mudderoy]

2000 XJ, replaced water pump, thermostat, cooling temp sensor, radiator, coolant, thermal fan clutch, and electric fan. Temp stayed about 210 after replacements. Electric fan does not come on at all, even when ac is turned on. Any ideas? All suggestions welcome.:confused:

You can test the fan by running 12 volts directly to it and bypassing the XJ's wiring. You could then put a piece of cardboard in front of the grill and let it heat up to the 218/220 range and see if it comes on via the ECM.

[gary63]

My 2000 elec. fan comes on at 215 or when the a/c is turned on and the temp. is at 195.

[nateyz2000]

I purchased an aftermarket adjustable thermostat that I wired my aux fan up to directly. The kit cost $17.99 from autozone. I can say that I have successfully fixed my running hot problem. I ran at 165 degrees all day on the trail. Woot woot! Any questions, pm me

Adjustable from 145-245 degrees or something like that...

[ranchand58]

Problem solved, I think. Figure this one out...Tried to test the elec. fan bypassing the harness w a jumper, nothing. Removed and re-connected elec. connection, nothing. Checked the 40 amp fuse, ok. Already had replaced the fan relay. So, I called my buddy who works at O'Reilly, went there thinking new fan was bad,($119) and I would get a replacement. Left the fan unplugged for the 10 mi. trip, drove w no ac, no overheating. My buddy comes out of O'reilly, plugs the fan back up and it starts running like a champ. Tested it for about 10 mi. before returning home WITH the ac running and it stayed cool, or at least it did'nt overheat, and been that way since.

My dash guage still reads a little right of 210 degrees. I still think thats too hot, but it seems to work although everything I've read and heard says the cooling system for this year and this engine is marginal at best. With 172K miles on it, I may just go ahead and do the elec. bypass w a manual switch, or the adjustable thermostat. Love the idea of running at 165 degrees the way another XJ'er mentioned, I think w an adjustable thermostast.

This car is my wife's daily driver and although it only 2 WD we love it. (won't make that mistake again). 4X4 forever...

Really thankful to all of you for your ideas, and suggestion. You guys have been more helpful than anyone I have talked to. Everything I've done to the car came from the suggestions and learning from this forum.

thanks...

[prerunner1982]

I am not sure 165* is a good idea either. The engine is designed to run at a certain temperature. At cooler engine temps the engine will dump excess fuel into the engine to try and get the engine up to proper operating temp. If the engine never reaches that temp you will see a decrease in an already marginal mpg. An engine temp of about 190* is good.

[Carves]

I am not sure 165* is a good idea either. The engine is designed to run at a certain temperature. At cooler engine temps the engine will dump excess fuel into the engine to try and get the engine up to proper operating temp. If the engine never reaches that temp you will see a decrease in an already marginal mpg. An engine temp of about 190* is good.


X 2 on a 190* temp. My scan gauge displayed temps, wander between 192* to 198* throughout the year - and fuel economy is fine ... 300 - 330 highway miles to a tank ... depending on whether Im wearing big boots or little boots .. :rolleye0012:

According to the vague info about the EFI system - in the service manual ... 165* is about the lowest of the "acceptable" operating temps, that the PCM wants to see for normal operation.

... so even tho its unlikely that the fuel injector pulsing will be at the "cold start / warmup" levels ... the PCM will probably be feeding the engine a bit more fuel than what it would at say ... 200*

Then theres possible issues of moisture/emulsion in the oil - If the constant running temps are well less than 180*.

[nateyz2000]

Let's hope I am off on my guestamation of what the needle says... Lol I hightly doubt it is 165... But needless to say, it doesn't run hot!