probably would throw a code if it is running rich and fouling plugs. In my experience running rich won't cause bucking on these cars. It can be misfiring due to fouling but that is usually a less severe misfire.
Former owner of '99 CSVT - Silver #222/2760
356/334 wHP/TQ at 10psi on pump gas!
See My Mods
'05 Volvo S40 Turbo 5 AWD with 6spd, Passion Red
'06 Mazda5 Touring, 5spd,MTX, Black
