View Full Version : Cold air when idle, but warm when engine stopped

02-22-2016, 04:17 AM
Does anyone have any ideas what could be wrong with my car? Warm air blows into cabin only with rpm's higher than about 1500.

The heat exchanger seems to be working because the air gets warmer when I stop the engine and leave ignition on. I also checked that the coolant flows fluently through it and to the right direction.

Thermostat should be fine because the coolant temperature rises up to 90 degrees and stays on that level. The heat regulation valves to the left and right sides of the cabin air function fine.

I also opened two of the three venting screws, but only fluid comes out of them.

Webasto heats the engine well but the air to the cabin remains cold.

No fault codes from VCDS.

The car is A6 3.0TDI 2005.