Replacing a thermostat on a 1989 Audi 100 should take an estimated 15 minutes. First you will need to disconnect the radiator hose by taking off the two clamps. Then you will remove the two bolts holding the housing in place. After the bolts are removed, the old thermostat can be taken out and replaced with a new one.
On a 1993 Audi CS 100, the thermostat is in the engine block. It is under the housing where the upper radiator hose is connected.
The thermostat housing is located on the passengers side of the engine block, behind the timing belt.
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Look at the engine end of the upper radiator hose
Audi 100
I am not familiar with the Audi, but on most cars, the thermostat is at the point where the top hose leaves the engine to go to the radiator. A bad thermostat can make your car overheat. If it has not been changed since 1992 it should have been changed long ago.
On my 86 Audi 5000 the fuel filter is located under the hood on the passenger side, up top and close to the inner fender. Yours may be the same.
I would expect $100-150.
Just like many used cars, an Audi 100 can be found at a used car dealership. One could also find a used Audi 100 at an Audi dealer or online at sites like Craigslist or eBay.
Audi 200 - 100% correct
Follow upper radiator hose down to engine block behind timing belt cover - 2 bolts ,, but tough to get at..drivers side .... Good luck ..
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