I was on my way to work and noticed my car started stuttering. Well when I got to work I let it idle and revved it up. No misses or stuttering. When I left work I made sure I was aware of how the car was running. It didn't stutter until it got up to temp. Would an O2 cause this? My mechanic said it would be monday before he could check it, but I would like to have some idea what's going on. It stutters in all gears through out the RPM's only under load. If I floor it I can't feel it stutter though. It doesn't stutter idleing even if you rev it up. Thanks