My x300 will not heat up inside. The car is running fine, all hoses are ok, etc., the engine gets to temperature but only the most feeble not quite cold air blows out of the vents, even at 30 degrees C. This happened, I think, more or less immediately although it never got really hot since I bought it, and I wonder if anyone knows what might be causing it, or what to check?.

Any help would be gratefully received!

 

My three best guesses would be.

1. A blocked heater core (quite common)
2. A stuck heater water valve
3. An inoperative heater water pump (either motor not working or impeller stuck)

For the heater core, try connecting some hoses to it and see if you can flush it out. If not that is your problem. It's a fiddly job to replace it.

Items 2 & 3 are easy to check and fix. Look here for a 'how to' Jaguar XJ6; Jaguar X300; Heater Pump

 

Thanks for this. Think it's a blocked core. So I have sorted it by ordering a ceramic heater! Will keep me going until I can sort it.

 

It's possible someone has changed the thermostat or a hose and the system needs bleeding