I have a 2006 A6 3.2 Quattro.

Recently the heating system has started to act up. I can set both driver and passenger sides to say 70F. I'll get hot air coming out the top of dash, cold on the passenger side and nothing on the driver side? (set to Auto)

The car will get really hot and if I turn down the drivers side then I get more cold on the passengers side, more hot on window and still nothing on the drivers side.

My mechanic connected to the computer and it said the secondary water pump was bad. None of the specs he has for the car (got them all from the local Audi dealer) has a secondary pump listed? The deal also said they don't know what the computer is referring to. They think it might be that Audi is using the name secondary water pump to refer to something else but they don't know what.

Anyone had a problem like this? Any ideas what might be causing it?

Thanks.

Pat