I've got a very annoying problem with my '85 Si that I hope someone can help me with. When I start the engine cold, it idles high (~2000 rpm). As the engine warms, the idle speed drops accordingly. Problem is, when the engine gets to normal operating temperature, the idle drops so low that it just stalls. It makes city driving a nightmare, because at a light or stop sign, i have to keep my right foot on the gas to keep it from stalling while juggling the brake and clutch with my left foot. And if I'm on a hill, its taking some super fancy footwork! I've been told that I might have a faulty Fast Idle Valve, and that the way to check this is disable it by blocking the mechanism with a solid gasket. This does not solve the problem. The engine won't run at all (cold or hot) by blocking the valve. Whew! Any suggestions?

try turning you idle and fuel pressure up just alittle bit that might help the problem and if it doesnt check the mass air flow sensor