My 2000 saab 9-3 just began idling roughly and the check engine came on. It runs perfect when driving, just has problems when idling. Any ideas?

 

Is the rough idle only happening on start up? Is it throughout the drive? How long has it been going on?

I actually picked up a 2000 9-3 last friday (11/12). I brought it home and noticed a rough idle only on startup for a few seconds and my check engine light is on. I was thinking it was the ignition coil. Took it to Autozone to check out the code and just as I figured it was an ignition coil problem. I would take it on over to get the code read.

 

I'd start with replacing the plugs. These cars are very sensitive to having the correct COPPER resistor plugs. Factory NGKs are best. Watch that gap, it has to be precise. The plugs are used to detect knock in addition to their normal function and fouled plugs will cause both a CEL and rough idle.