Hi I have a 92 fire bird , just got.it. Ran fine, idled a little high, but after a bit, it went down. Now.when it.idles, it just wants to.die when I come.to.a stop at a red light or stop sign. It.dies, unless I keep one.foot.on.the brake and another.on.the gas to keep it.idled up.
If you’re able to prevent the engine from stalling while stepping on the accelerator and the brake pedals at the same time usually points to a dirty/defective Idle Air Control valve.
Tester has a very good point, something of that age 90% of the time has built up several deposits within the engine and intake system. I always recommend running a can of fuel system cleaner through it and an engine oil sediment flush just to help take care of these problems.
But aside from that I also have to recommend checking that you do not have a vacuum leak.
Sometimes a simple vacuum leak can greatly affect your idle and your car will exhibit the symptoms you describe.
Hope these might help fix your problem,
V6? 3.8 or 3.4?
In reviewing my previous post I did notice in my agreement with tester I did not mention that the can of fuel system clean will NOT affect idle air control which is located higher up in the plenum.
To clean the idle air control grab a can of throttle body cleaner from the local auto parts store,
then disconnect the air intake duct work leading to your plenum, you can probably just separate the intake right where it connects to the plenum body itself as long as it has enough slack to move freely just dont break anything when you move it aside from the plenum. spray the can right at the throttle body in the plenum and clean all the black gunk away from the valve then open the valve and spray more into the plenum intake passage again just clean around the valve including the edges that reside next to the outer wall and any passages you see inside the throttle body. Reconnect the intake and double check to make sure all is connected exactly as you took it off.
start up the car and see how the idle is after.
Hope that helps,