Heater does not run warm at low revs

[lesxk8]

After the garage replaced the top Lambda sensor i have been having problems with the heater temperature. I suspect they may have broken down the cooling system and allowed air into the heater matrix. I have driven the car a few miles now but it wont clear by itself. Is air in system likely and if so what is the best way of clearing it?

[Jimbov8]

Park the car so it is pointing slightly uphill. Take the cap off the reservoir and then allow the car to run up to temp at idle. When the stat opens the coolant will flow around the system and the car will burp itself at the reservoir.

[JOE-DOT-COM]

hi

there a produre to de-air it, you usually need to do it cold, with ignition on

they have a aux pump that assists when the engine is idling

cheers

Joe

for proper filling and bleeding workshop manuals are here http://www.jagrepair.com/

[lesxk8]

Thanks for the info. I shall first try the bleed on an incline and then check out the auxiliary water pump.

[lesxk8]

I have carried out the incline bleed technique and it certainly has made a difference. The heater now only runs cold when the revs are below 1000rpm. This will do for the time until we get out of winter and i can find where the auxiliary pump is hiding.

[Jimbov8]

40 minutes ago, lesxk8 said:

I have carried out the incline bleed technique and it certainly has made a difference. The heater now only runs cold when the revs are below 1000rpm. This will do for the time until we get out of winter and i can find where the auxiliary pump is hiding.

An improvement sounds good though I would say you still have some air in the system. If you can live with it then fair enough, but do keep an eye on the temperature gauge if you go on any longer runs.

[Richard A Hughes]

Hi Les. My 2003 XKR developed a problem similar to yours recently. The heater started only working if the engine revs were >2000rpm. Even then, only just. Also found the front fogs weren't working and traced to a blown fuse no3 (5amp) in the under bonnet lhs fusebox. This little fuse operates the relays to both front fogs and the heater pump. So I replaced fuse which of course, just blew again. Looking closer, the same fuse also operates the 'intelligent sounder'. It's security gismo which alarms without need for a battery and is located in the front rhs wheel arch, accessible from a wee hatch in the wheel arch liner. So I pulled the connection off the IS, replaced the fuse and my heater pump and bingo! front fogs are back in business. I can run without the IS and may just leave it out altogether. Any help to you??

[Richard A Hughes]

Just noticed a typo in my last message. I didn't replace the heater pump!! Should have read .. and bingo! my heater pump and front fogs are back.. Apologies..

Richard