No, this is a timing belt. Serpentine belts don’t have teeth like a timing belt; they have ribs instead. You can see where the serpentine belt would normally sit on the crankshaft. The serpentine belt would ride on the ribbed pulley that sits just below the red pulley in the picture.

Audi built by vehicle are said by vehicle mechanics as the worst car ever. They don’t own them . They buy Toyotas

Sounds like the water pump isn’t turning correctly, or perhaps the thermostat isn’t opening.

I had this problem with my 97 honda civic. the car won’t start. I checked regular items: battery, starter, spark plug wire, distributor cap, rotor, and electrical connections etc. all in vain. i’ve never seen this problem before. After a few days of intensive research, finally i found a piece of info that says worn timing belt can cause the car not to start. my car’s timing belt is not broken, but maybe worn cause it’s running for over 80k miles. so i opened the timing cover and found the timing belt tensioner is loose, not putting pressure on the belt, timing belt is still OK.

Defective tensioners are common with many Audi’s. Being a inteference engine that’s all it takes to destroy valves and pistons. The problem was so bad Audi issued recalls and class action lawsuits were filed. I never buy a used vehicle without a quick google search for KNOWN defects and reliability history ! Recently interested in a beautiful Nissan that looked immaculate and ran drove perfectly. Very first previous owner comment “the biggest POS i have ever owned” followed mostly bad but mixed reviews. I’ll take their word for it. Sorry to hear about the car, I know the sick disgu$ted feeling all too well.

What causes this noise