idle problem!?!?!

[marinepolice03]

91 L. stock motor.
when i hit the brake when i am at a stop the idle goes down to 500-700? what could it be? thanks.

[freshtiva]

Does the idle drop just because you hit the brake? 700 RPM isnt too far from the correct idle.

[marinepolice03]

it will sit at 1000 untill i hit the brake than it will drop a lot and sound like it wants to die.

[freshtiva]

Is your car an automatic or manual? L, probably a five speed?

[ajb999]

mine idles at around 400 when it is warm in neutral or w/ the clutch in but the brake doesn't affect it.

[mooseheadc]

Re: idle problem!?!?!

91 L. stock motor.
when i hit the brake when i am at a stop the idle goes down to 500-700? what could it be? thanks.

do you also get a drop when the car has been in neutral for some time,

or does the drop vary if you pump the brakes.

If so, you might have a leaky PB vacuum booster

[marinepolice03]

it is a L, 5 speed and it does drop after sitting in neutral for a while. when i started it this morning it went to 2000 than droped down to 700. whe i hit the brake it went to below 500 than died. ?? could it be the pb vacuum booster? if so how hard are they and what is the average price for one?

[Dave G]

could it be the pb vacuum booster?

That would be my guess. Simple test would be to remove the hose from the manifold, plug the opening, and see if that fixes it...

[marinepolice03]

thanks !!