I have a 1999 XK8 with 62,000 miles on it. I've owned it about a year and I've always noticed how much heat the engine puts off. The temp gauge never moves from the middle, but the engine is HOT. With the top down you can feel the heat coming off the engine. On a hot night a 10 minute drive makes the fenders almost too hot to touch.

When I lived in a cooler climate this didn't seem to be a big deal. I've moved to a warmer climate and it seems to be becoming a problem. The car starts and runs great in the morning. If I make a few short trips, leave it in a hot parking lot, then start it, the engine idles very roughly and the restricted performance light comes on. After half a mile or so the light goes off and the car runs ok.

My 2006 X-Type Sport didn't have this problem. The 2005 XJ8L I drive every day doesn't have this problem.

My question to other XK8 owners is... Do your cars seem to run this hot?

Thanks.

 

Wow, mine never gets that hot...but I do notice it from time to time.

If you're even remotely worried about it, spend $40 for a new thermostat, flush the radiator yourself (theres a new DIY document we just added to the FAQ page), and relax.

If you're really ****, find an OBDII scanner that monitors real time data, that can read your water temp, the gauge in the dash is just a 'go by', its either in the middle, or it spikes..then its almost too late.

 

I have felt that issue too. Yesterday, for no reason, i had a little steam coming out from the passenger side of the hood. By the time I got out to look at it ... it stopped. Did not do that today and my temp gauge never went above normal. Next free weekend I will do the flush and replace thermostat just to be sure while I change the oil also. Gee... now that I said that.. I have some work ahead of me!

 

My '98 seems to run warm too and on a hot day you can count on the electric fan coming on within 20 seconds when stopped for a light or after shutting off the engine (keeps the garage nice and toasty in the summer!). The temp gauge never reads hot though. Is your electric fan operating correctly?

 

Thanks for the replies. I've had the thermostat replaced and the fan comes on frequently, so I believe it is working.

I'm not sure when the last coolant flush was done though. That would be an easy thing to try. Thanks for the suggestion.

I'm also not sure if the water pump has ever been replaced. Could an aging water pump contribute to these symptoms?

I spoke to a Jaguar mechanic this morning (independent, not dealership as the dealer hasn't found the problem so far). His suggestion was that the rough idle when hot may be a plug going bad. Apparently hot conditions can cause that in these cars.

 

seth, the 4.0 engine originally came with a water pump with plastic impellers, didn't last that long in that engine. Worth a look, for preventative measures and peace of mind.

 

It's quite easy to replace as well. Like H20 said the pumps have plastic impellers which have a tendency to rot. Mine has been replaced twice and the car has 64k on it currently. Secondly, if you see some white in the coolant it's definitely time for a flush. Thirdly, the temperature gauge in the car isn't a linear gauge. Meaning as long as the temp stays between x value and y value it just doesn't move.

 

Good advice all. Thanks!

 

You know Brobin, Now that I think about it... I have NEVER heard my fan come on?? Is there a way to test the electric fan?

 

mine immediately comes on whenever I start the A/C, I think that's standard for the fan to do that. Then a high-speed level kicks in when needed.