Actual COMMON Problems are:
Wheel Bearings
MAF if it's not a Hitachi(sp?)
Front Suspension (Control arms and Tie-rods)
Transmission grinding (Syncros)
Turbos if the car hasn't been properly warmed up/cooled down.
Pixilation in the gauge cluster computer
By-bass valves ($100 fix) usually only go bad with chipped cars.
Other stuff that should be addressed at or around 80k is the timing belt, O2's and clutch will probably be coming up.