Fast idle problem

[Mark Ergetowski]

You can adjust the Fast Idle Air Valve by knocking out the frost plug on the throttle body and turning the valve seat with the end of a pair of needle nose pliers until you get the desired cold idle speed.

On cars with the throttle body water lines bypassed you'll need to close off the FIAV completely otherwise it will never go out of fast idle mode.

Cool is good, but I will add my .02: by bypassing the warmup circuit and blocking off FIAV your car WILL be stalling while cold.

To prevent that, I've installed an auxilliary air bypass controlled manually by the driver (mostly me   ) The whole thing is set up on such a way that I can add enough air to rev it up to 1500RPM cold and 2000RPM warm.

I suppose one could set it to fast idle while stuck in trafic and listening to loud music too      

Here's picture of the air lines in the engine bay:


And this is the valve:


I hope it helps

[John Hartman]

that is actually pretty well done

If you need it, your solution would be very cool.

I have had my fiav blocked off for over a year, and its never stalled, not once, cold or warm.

I suspect a car that stalls would need to have its ISC cleaned and the BISSS set so that the ISC has enough authority to do what it needs.  If its at its stop, either all the way out or all the way in, it can no longer control in that direction.  Hence the BISSS set adjustment.  This procedure centers the ISC stepper.

[Lowell Foo]

You can adjust the Fast Idle Air Valve by knocking out the frost plug on the throttle body and turning the valve seat with the end of a pair of needle nose pliers until you get the desired cold idle speed.

On cars with the throttle body water lines bypassed you'll need to close off the FIAV completely otherwise it will never go out of fast idle mode.

Cool is good, but I will add my .02: by bypassing the warmup circuit and blocking off FIAV your car WILL be stalling while cold.

To prevent that, I've installed an auxilliary air bypass controlled manually by the driver (mostly me   ) The whole thing is set up on such a way that I can add enough air to rev it up to 1500RPM cold and 2000RPM warm.

I've blocked the FIAV on many cars.  It will not stall if the ISC is working properly and the BISS screw is properly adjusted.

[Mark Ergetowski]

I've blocked the FIAV on many cars.  It will not stall if the ISC is working properly and the BISS screw is properly adjusted.

That's what I thought but mine was stalling so I had to do the bypass. My warm idle, timing and all that is adjusted as the book says, so maybe it's just my car??? I dunno.

[Lowell Foo]

I've blocked the FIAV on many cars.  It will not stall if the ISC is working properly and the BISS screw is properly adjusted.

That's what I thought but mine was stalling so I had to do the bypass. My warm idle, timing and all that is adjusted as the book says, so maybe it's just my car??? I dunno.

Just noticed your car isn't a turbo, so that could be the difference.

[Mark Ergetowski]

Just noticed your car isn't a turbo, so that could be the difference.

It sure makes a whole lot of difference....... :laugh:  :laugh:  :laugh:  :laugh:  :laugh: