The fuel pump relay is located on the engine driver's side of the firewall. It is held by a bracket with two other relays-primary and auxiallry fan. The fuel pump relay is between the 2 relays. It should have a test lead extending from the connector.
It is listed in the 1991 Pontiac Firebird Operations Manual
What parts??? Body, engine, suspension???
The VATS resistor on your key may be bad, or inside your steering column.
I calc'ed my '91 V8 Formula Firebird to be about 18 mpg.
i know the backs are 6x9
A firebird can't "have" third gen. It either is or is not a third generation firebird, and Yes, a 1991 is a third generation.
underneath the drivers door
I know mine is on the drivers side there is a door in the kick panel
I use 10W-30
I have a 1990 Pontiac firebird, and the gap on that, I believe is .035. If you still have the sticker under your hood with the engine size, it says it right on there.
A wiring diagram, for a 1991 Pontiac Firebird, can be obtained from most General Motors dealerships. The wiring diagram can also be found at most auto-parts stores.
Roughly 4.5 quarts with a filter change.