[cg084]

Hi all,

I have an A6 4.2 V8.

It takes ages to get to temp 1/2 way when starting from cold.

If i put the heater on temp drops to about 1/4 on the gauge.
If i turn the heater off it comes back up.
If i stop in traffic it comes back up with heater on.
If i have the heater off it get to temp after about 10 mins and stays at temp til i coast the car for a distance.

I did have a very small drip leak from the expansion tank and small rad hose that connects to it. At the time the gauge went up to 1st notch after 1/2 way. Noticed immediately and put heater on full.

I replaced the hose and expansion tank.

Since then have had the temperature falls. I have replaced the Thermostat, water pump and 2 temperature sensors. There has been no change. The car is not using water.

I do notice a temperature drop in the heater air when this happens.

I think its an Air lock in the system but the specialist does not agree as they think it would cause overheating.

Does anyone have any thoughts. Also if anyone has any pictures of the bleed valves that are on the 2 pipes going to the heater blower matrix.

Cheers.