ericliquid

The shop I went to wants to replace the whole water pump and thermostat assembly(parts is about $300,special order), and quote me $650 for the whole job. Is it a fair price?

The guy said this is a common problem of b8 audi and it is better to replace the whole assembly than just the thermostat (parts is $75,special order) alone, which is more labor intensive.

Diogenes

A few months ago I had an independent replace the thermostat only on my B7. Parts about $80 and labor about $450. The problem is that the shop has to pull the front end off the car to access the thermostat and water pump. I only did the thermostat because I anticipated a timing belt change in a year or so and would do the water pump then. The B8 doesn't have a timing belt so that's not a consideration. Doing the pump and thermostat at the same time would save the cost of pulling the front end a second time. Go for it. It's only Geld.

Moviela

You can buy a pump for about $120 from a replacement maker of pumps, and a Behr thermostat is inside. It takes a while to change the pump because to do it right the intake manifold needs to come off. While it's off you might as well decarbonize the intake valves.

Took me two hours, but I cheated and used a walnut shell bead blaster to remove the carbon after soaking in BG44 sauce. The B8 has the pump driven off the balance shaft at the rear of the engine, so pulling off the front is of no use to change the pump. So guys have changed it without removing the intake, but they have smaller hands and are more buff than be.