my car has had some intermitent running problems, it will occasionally idle rough(like its on 5 cyl only) surge and hold idle around 2000rpm, then misfire/stall, and will not rev while doing so. last night it did it again, I got it home, but it wouldn't shift above 2nd(auto) so I drove home @ 3000rpms(sucked). the anti-theft light will often flash while its doing this, then all the sudden it runs fine. it does always run rich anyhow. The IAC is fairly new, I just cleaned the Maf sensor and IAT. what are the symptoms of o2 failure? could it be an anti theft issue? the only code its ever thrown was a 1512, which 96gt's don't have runner control. any ideas?