I have an Audi 80 4dr and it has been great. I bought it used and the previous owner didn't take good care of it. I replaced some stuff and even though it was a little hard to find the parts it was all worth it and now it's going strong.
Audis of course are all pretty good cars. Lately the new 1.8T A4 have had some problems but not the older Audis. I really enjoyed owning this Audi but it's definitely a money spender. I had to replace the transmission at 197k miles but other than that no other big replacements. It has 199k right now and is running strong. The gas mileage is pretty good and the power could be a bit better. Just make sure you get the car fixed by good professionals. Overall a good car!
BarelyG-- To comment on your question 1, to my recollection the 1991 Audi 80 quattro does in fact have a 5-cylinder engine but I believe it was a 2.3L not a 1.8L and had a horsepower rating of only 1...
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