My 1998 XK8 appears to be overheating, but only occasionally. If I get it up to temperature (5-6 miles) driving, I will smell antifreeze (on occasion) and upon shutting it down the fans will run at full speed, engine is hot, it back flows a quart or so of radiator fluid. The CEL then says its overheating. However the temp gauge shows its at normal temp. Once it cools down, it usually appears OK, CEL message clears after a few minutes and all is good for a week or so.

Could the thermostat be intermittent? I'm fairly new on the forum. Living in Sebring (without a Jaguar shop) my options are limited for getting local help.

 

#1 Don't trust the temp gauge. If your water pump hasn't been replaced, the vanes are probably gone. Don't let it overheat. I'm sure others will chime in.

 

The V8 thermostats seem to stick CLOSED while the AJ6/AJ16 t-mostats stick OPEN.

We had trouble with the early V8 cars at the dealer in the late 1990s.

 

The gauge is useless as after it gets to normal it is computer controlled ,,Get a P10 heads up display.
I have had a right " thermostat trauma"
All fine reading 88C ( 84 deg stat) booted off the lights cause I was a bit slow seeing the change and wam went up to 98 and would not come down ...1/2 mile from home OK.
Ordered a new stat only availabe as off to france the next day rated at 80c by gates.
Well it was fraud or fake .the temp varied from 86 to 98 and when stuck in traffic had to turn off the air con to get it down .my fans are on half speed 24/7.
On return fitted a 84c by Waxstat and all is well.
Yes in the old days failed open ..I think there was a mechanical latch to hold it open, Not so today.

 

My 1998 XK8; the thermostat stuck closed at about 20k. I turned the inside heat/fan on full and was really close to home, so I think I lucked out.