When my Firebird was doing the same thing I tried a new bulb and it didn't work. So I bought a new rear pigtail and put that in. Works like a champ now.
...Or replace the flasher unit - about $5 at Wal-Mart. Usually located on the driver's side under the dash; silver, round, three prongs, about an inch tall.
when that happened to me, i simply reversed the bulb i was putting in.
two silver beads on bottom bulb insert....like, batts...+ and -... try turning the bulb,
before putting it in.
If the turn signal bulbs work but just do not flash, replace the Flasher Relay.
HOW DO YOU GET THE LEFT TURN SIGNAL BULB OUT ON A 2000 PONTAIC FIREBIRD
You could be hitting the flash feature on the turn signal arm when you use it.
How to change blinker switch in a 1994 Firebird ?
Turn signal indicators are lights. The flash to tell you, or indicate, that a turn signal is on, and which way the lights are flashing.
where is the turn signal flasher on a 1996 lumina sedan
Location of turn signal relay on mercury 1996 mystique
You need to replace the turn signal bulb. When bulb is burnt out the turn signal will flash faster.
under the driver side kick panel
Part of the hazard warning module
Burnt out bulb.
If the bulbs check good, replace the flasher relay.