Heater blowing cold, Temp gauge moving up and down

All your other probs if any.
RetroPKR
Posts: 4
Joined: Sat Jan 27, 2018 12:00 pm

Heater blowing cold, Temp gauge moving up and down

Post by RetroPKR »

Hi All. 2005 model 1.6 petrol Auto

Heater blowing cold air. On the motorway yesterday (3 hour run from work) I noticed the temp gauge was high for twenty seconds then dropped to normal/low for twenty seconds, then back up to high again, and repeated the cycle all the way home,
Header bottle level is between min & max. Nothing unusual from exhaust pipe or on dipstick,
Engine does not seem to be overheating, but blower is cold and the gauge needle is up and down like a fiddlers elbow !
I unscrewed the bleed screw on the heater pipe and lots of fluid came out but no "hissing air noise"

IanL
Posts: 1526
Joined: Wed May 13, 2015 10:34 pm
Location: Jersey, Channel Islands

Re: Heater blowing cold, Temp gauge moving up and down

Post by IanL »

There are two bleed screws - you need to check both.

Just a guess, but your water pump may not be working. You will still get some engine cooling by convection. I have heard of the pump shaft fracturing, or the teeth on the pump impeller corroding away.

If you do decide to check the pump, you may as well change the cambelt at the same time.

RetroPKR
Posts: 4
Joined: Sat Jan 27, 2018 12:00 pm

Re: Heater blowing cold, Temp gauge moving up and down

Post by RetroPKR »

Thank you