heater blowing cold air please help!

[dannyoct16]

my 98 A6 only blows warm air when im driving. when im at a stop light it starts blowing cold air again. i live in cleveland,ohio and ots been cold. ill warm up the car for 15 minutes and get in to a cooler!! ill start driving and the heat kicks in. has this happened to anyone or does anyone know what the deal is?
thanks,
danny /ubbthreads/images/graemlins/cry.gif

 

[audi5e]

sounds like the water/coolant is not circulating properly.
when last was the coolant system flushed?
check the level too.
may also be a pump on it's way out?
some models have a valve in the inlet pipe to the heater matrix, make sure this is opening/functioning properly.

 

[dannyoct16]

thanks..ill check it out!

 

[snates]

Weak waterpump or poor circulation through the heater core