Heater Problem - Help Needed ASAP

[dubfreaks]

2001 - A4 2.8L Automatic.

The car blows HOT when Idling. But when driving, it becomes warm, not hot, like it should be... Suggestions? I have customers waiting on this car and already sold them the car... Trying to fix it for them for their long commute.

[Tugboatguy]

What's the temp gauge doing ? Is the gauge reading normal?

[dubfreaks]

Well, it's either the water pump or heater core.... time to replaced the pump (5.2 hour job)