I have a Audi A6 2.7t with 94,xxx miles, and i have no heat when the car idles.
Things i have done to the car in the previous year
1. Rebuilt Transmission
2. New Turbos
3. Water Pump/ thermostat
4. Timing Belt
5. Valve Cover gaskets
AND more Suspension wise
I love my Audi even after doing all this in the past YEAR. The onlY thing is that there is no heat when it idles. I blow the heater core out still no luck. However the car did have the same problem even before the water pump and thermostat were done.

The only thing is that i could see a small antifreeze leak that i think its coming for the intake manifold. The car does not over heat or anything nor i ever had to add antifreeze to it. Could a small leak such as that cause the car not to have heat at IDLE?

 

Hi! What do you mean you blow the heater core out?

I would check

0. check errors for climate control systems (flaps like temp, etc.)
1. in, out pipes to the heater are both hot (can't touch)
2. no air in the system (bleeding screw)
3. if no air, in hot, out is cold - replace heater core

 

There's no coolant anywhere near the intake manifold.
I agree with Maxim's steps.

 

While there isn't any coolant in the intake manifold, there is UNDER it. The Aux coolant pump and connecting lines are in the valley under the intake manifold. They do go bad and leak...

This should not effect heat to the heater core. I would suspect air in the system.

 

Also check out this link: http://forums.audiworld.com/showthread.php?t=1730710

 

Mike, I totally agree, as both coolant lines going to rear of the WP and Tstat housing run indeed under the manifold.
However, he said "for the manifold" (I would assume he meant "from the manifold" ). Moreover, you know that the only places the pipes could leak anywhere near the "manifold" are exactly at the housings (the rubber O-rings getting weathered due to heat or whatever), and that's way below the manifold... You can only figure out the leak by shining a light in the valley pan area, in between the Vacuum reservoir, edge of the exhaust manifold bottom, and engine block. If it is anything pooled in there, then it is either coolant or even oil if you have a leaking valley pan gasket.
The other potential leaking spots are nowhere near the manifold: rear of heads, and the joint point of the main rear coolant pipe with the hoses that come/go to the heater core.

On the other hand, I understand what you're saying about the Aux Coolant pUMP (sorry, I typed pipe)- which I don't have in this 2.8, and while I still doubt a leak anywhere there could be considered to be a "manifold" leak, I want to point out that we're actually on the same note:
tks.

 

My A6 does not seem to make much heat either when idling with the temp set to 70o. However, punching them up to HI and turning the fan on all the way makes a difference. Give it a try and advise. It seems to me that the automatic temperature balancing restricts that blast of hot air we remember from other cars.

 

Check out this thread as well...
http://forums.audiworld.com/showthread.php?t=1730710

 

haha, read above! copy cat

 

After taking the intake of the engine i find that the hose directly under the intake had a small coolant leak. fixed that and put the intake back on. drained the coolant out completely. Tightened everything up and then I bled the system. I did that by the bleeding screw in the upper part of the engine and at the heater core. The car does not overheat but there is still no heat at IDLE.
Any other advices
Things i did so far
1. Water pump
2. thermostat
3. fixed the leak on the hose that was located directly under the intake manifold
4. drained old coolant put, put new coolant
5. bled the system
6. bled the heater core following instruction from the page http://forums.audiworld.com/showthread.php?t=1730710

I have also realized that bottom hose on the heater core (inlet) gets hat and seems like there is some pressure. But the the outlet is not under pressure and its not getting hot until you rev the car up for sometime.
Any suggestions on what i should do next?