Here comes the misfire thread again :P

anyway, I had a really nasty misfire recently that basically dumped raw fuel into the exhaust piping. Didn't matter whether the car was warm or cold, it'd start missing badly and backfiring even after the engine was turned off. I could hear fuel detonating inside the exhaust pipes. I had to drive it around like that for about ~30 miles.

I replaced the optispark and the problem got a LOT better, but.....

I pulled the driver side o2 sensor and (of course) its black. The motor misfires when the driver side o2 sensor is plugged in, ONLY the driver side. Would a dead o2 sensor cause a misfire like this? The motor misfires only after its warm. I re-soldered an extension for the o2 wires and there's def. continuity in each wire, but i **think** the problem is deeper than just wires.

also, do you guys think that I need a new catalytic converter?

bleh.... more money