car idle drops and car dies out when at stop. on 1993 Chevrolet Lumina

when im driving the car its good but when i stop at a traffic light, the idle rpm's will drop to 500 then shut off. but if i hold the brake and put a little pressure on the gas pedal the car stays on.and when i got it home i let it idle for a little with it still in drive and it was fine, but the rpm gauge was bouncing just a little, like it wanted to die. I did alternator check(good) load test on battery(good), and the spark plugs look good also. so what could it be?

by in Seattle, WA on October 08, 2013
2 answers 2 comments
ANSWER by on October 08, 2013
I think it is IAC (idle air control valve). It locates near the air throttle body. removing two bolts and the IAC can be taken out to check or replace. Also check if the air channel is clogged. good luck
COMMENT by on October 08, 2013
where would the air channel be located?
ANSWER by on October 08, 2013
I assume there are no computer codes or check engine light on SO, clean, or have cleaned, the throttle body and 'back' side of the plate (butterfly) with carb. cleaner and a toothbrush. Then be sure all air filter componets are in good shape, in place and tight.!
COMMENT by on October 17, 2013
so i cleaned the throttle body and IAC and it still does the same thing? any other idea? i did a fuel pressure test and i came back good.