Newby for the Z3 arena so sorry if this is a repeat question. Just bought a 2001 Z3 (3.0). I might have a chance to get a free set of old snow tires/rims for a 2003 Z4 (3.0)...would these fit on the Z3?

Also, "service engine" light comes on for a day or two, then will go off for a day or two. It does not flash. Initially the dealer (chevy) said it just needed a new battery and it was replaced. A week later, light came on for 2 days, now its off again...any advice?