high to low idle
 

Hello,

I have a 88 Grand Marquis thats devloped a problemsom idle. When I cold start it, the car starts to idle from hi to low from hi to low, some times it just won't stay running. I mean it will sound like its about to go then it will just stop. I've changed the spark plugs, wires, the fuel filter, and the cleaned the cap and rotor bug. I tested the coil and it tested out strong. I'm completly clueless as to what caused it to start doing this and what to do to remedy it. any suggestions??

thanks

sounds like the Idle Air Control Valve (IAC) is gummed up and sticking. you can use a carb cleaner to clean it up after taking it off... it is a silver looking cylinder on back side of throttle body with wires off the bottom. it is held by 2 small bolts.