[s-cars] New-to-me '92 S4

[David Giannandrea]

This would just be a guess on your symptoms:

Noise: might just be tires. I had this problem with my car, it would take
about 20000 miles to wear a wave into the outside edge of the front tires
and then they roared. Finally found the problem in a control arm... after
replacing shocks, subframe bushings, strut bearings.

Engine light: When I got my car, at about 100000 miles, the MAF was failing.
It ran just fine, no loss of power or mileage, but did die on occasion when
letting off the throttle in neutral. Other possibles (not personally
experienced) might be plugs, coil packs, injectors (can be cleaned, check
google). I know from experience ( my friends A8) that cheap gas will foul
plugs and throw misfire codes.

Good luck,

David