I've noticed the coolant fans running continuously when i turn the car off and when its running, even though i'm not running the a/c. Is there something going wrong that i should be concerned about?

 

Could be worth looking at the thermostat it might be sticking

Possibly a faulty Fan Relay

 

It would help if you would post your model and model year in your signature or avatar.

The fans are controlled by the temp sensor in the upper coolant plastic pipe on an XK8 reporting to the ECM that fans are requested. The ECM operates two relays to turn on one or both of the fans.

First GUESS is that you have a temp sensor failure, cheap solution but just remove the wiring connector and see what happens.

Second GUESS is that you have a sticking relay.

 

Sorry...i have a 01XK8. where can i find the relay.

 

Sorry, been out riding the other toy. Beautiful crystal blue skies, 70 degrees in the Georgia mountains.

I see you re-posted and got an answer. I would suspect the temp sensor first. Pull the connector and see if the fans run. If they do not it is the sensor.

 

flush the radiator to clean it out, put in the new fluid along with a little water wetter and change the thermostat and you're good to go

 

When mine started doing this on my 02 XJR @90k, the car started overheating a few days later. Replaced coolant, waterpump, and thermostat all at once, and the fans stopped running all the time.

 

Yep, I am experiencing the same issue with fan running after turning off the car.

Can someone provide a video on replacing water pump, thermostat, getting the hood off the car? Even better, video for the 2nd tensioners on the XK8/R. That would benefit us less gifted. Rev Sam?

 

JagYi,

Was looking for XKR cooling stuff tonight, came across these links, thought I would share.

Very detailed coolant and thermostat replacement instructions:

http://matt.zenfolio.com/xk-coolant-...tat---v1-1.pdf

Discussion of plastic vs metal thermostat housing

https://www.jaguarforums.com/forum/x...housing-13871/

Instructions on how to make the hood go 90 degrees up without removing it, and more t-stat housing discussion:

https://www.jaguarforums.com/forum/x...housing-13044/

Frequently asked DIY / maintenance questions:

https://www.jaguarforums.com/forum/x...ts-data-29800/

And while in that area, can easily do the main drive and supercharger belts (esp since if they get coolant on them, they will be poisoned and start squeaking) :

https://www.jaguarforums.com/forum/x...acement-42373/

https://www.jaguarforums.com/forum/x...er-belt-41502/

I did my waterpump from instructions in the JTIS. Can't find it just now for the XKR, but it was avail for XJR in the forum. Haven't made JTIS work for me on Vista64 yet, that is my next Jag project.

hth,

 

Wow, nice links! Thanks!

Now I have no excuse but to work on the car one of these days... hah.

 

No problem.

To be fair - test point is right, analysis is required. I just threw parts at my car because I was refreshing the cooling system.

The problem is that I just got lucky. In my professional life as a database performance guy, I often warn people against just guessing like I did. It often results in lost money, wasted manpower, and a nasty blamestorm if it doesn't work out.

But, I am unsure exactly how I would have assessed it. I guess the first thing I would have done would have been to independently determine coolant temperature. I suppose another test would have been to boil the thermostat to see if it opened and stayed that way.

Unsure how to test waterpump flow.

Have a good day, all.