Audi Repair: Audi A4 cold air, No heat?, audi a4, heater core

Question
I have an Audi A4 2.8 Quattro. I have air pressure but it is only cold air and no heat at all.  I was told it was heater core or it was electrical?  please help!!!

Answer
Could be the valve controlling the hot water into the heater core.  Check that valve it is located under the hood, in the middle behind the engine are 2 3/4-1" hoses next to each other, one has a valve in it.  Also check both hoses should be hot when the engine is warm.  It may also be worth it to the flush the cooling system.