I only just noticed this - it was quite cold this morning, i was waiting on the car heating up when i realised that even after say ten minutes of driving the heating was only luke warm even with 31 showing on the display ... i checked the water level on Monday it's not that - sounds like another easy fix - any quick ideas? Cheers.

 

1. make sure the In-car Aspirator isn't blocked (arrowed in red) or the sensor covered in dust



2. try cycling the A/C from max Hot through max Cold and back a few times. If the PO has left it set in the same place for a lengthy period, the flaps can stick.

3. check the heater water pump is operating

Graham

 

My 01 does the same thing and the colder it gets, the cooler the air. I can set the temp to 80 and it will not get real warm. Have not tracked down the problem, but when I turn off the system, I can hear the blend door close.

thinking either the coolant is not getting hot enough (when it is 60F outside the air blows hot) or maybe my heater valve is sticking or heater core is partially blocked or going bad.

 

The most common problem seems to be the coolant pump as Graham identified. The hot coolant will circulate through the heater core without it while driving but not so much idling.

 

Prepare yourself for a world of pain.

https://www.jaguarforums.com/forum/x...val-how-96841/

 

I was having heating problems with my wifes 1997 XK8. the only way i could get heat was to set controls to HI and then it would warm up. The fix for mine was the ambient air sensor. I happened to accidently bumped the external temp button one day and the readout said 136 degrees. i replaced it and now i can set for 74 degrees and the temps controlled automatic. Bought mine from Jagbits received it in the mail in a couple of days.

 

will check it out - this baby seems to just need to be used again. I think it's prob been left in the same position temp wise for a long time - here's hoping

 

One other possibility, albeit remote, is if the antifreeze was changed lately. The heater system will air-lock and it's necessary to set the control heater on full hot and run the engine at ~3000 rpm for about a half minute until you feel good hot air coming through (wait until the car is fully warmed up before you do this). This flushes all the trapped air from the heater circuit. If this solves the problem, then after the car completely cools down you would need to top off the coolant.

If it doesn't solve the problem then you're back to either the heater pump, or valve, or sticking air control doors.

 

when it's up full it's warm enough, i think it may well be an anti-freeze issue. It's not been that cold in London this winter - it's not even snowed once ... thanks guys.