Ok, so here goes.
1990 V6 3.1 Firebird Automatic:
I recently had a problem where slowing down to turn or at lights would
stall my car and sometimes when warm the car would crank and start but
die immediately. First thing I checked was Ignition Module, Advance
says its good (I'm not so sure). Then I replaced the IAC. Well, I
didn't realize the Ignition Module came off of the distributor w/out
removing the distributor, so I had to reset my timing. I disconnected
the wire like the Emissions sticker said and set the car for 10* BTDC
at idle. Now I'm getting a rumble from underneath my car. It feels
like its coming from underneath my shifter knob, which makes me worry
that there is something very wrong with the transmission. Could that
be engine knock/ping or backfire? Maybe my timing is wrong?