Tried a search but none of the problems seem the same as mine, so here goes:
B6 2010 highline estate, lots of miles and recently had timing belt and water pump done at a very good/respected garage with no apparent issues.
It’s been very warm here recently so since I got the car not had to use the hot settings in the heater til last couple of days.
If I put the setting to hot it will blow hot air for a few seconds then drop to mildly warm then cold.
If I rotate the control to cold for a second or two then back to hot it will go warm-to-hot again but only for a minute or two then drop back to cold.
Can repeat this as often as you like right after doing it and same result, so you can sit yo-yoing the controls and get warm air.
The car is not losing coolant, there’s no apparent oil mixing either in the coolant lines or in the engine and dipstick so don’t think it’s a blown gasket but at a a loss what’s causing it.
Oh and the AC switch is set to off.
Before I start ripping things apart to try and flush the system has anyone any ideas?
Need to sort it soon cos it gets pretty cold over winter up here in sunny Glasgow
(And thank the big man upstairs for heated seats!!)