Does your Ford Escape / Mercury Mariner crank but won't idle properly? Does it die at stoplights or when you take your foot off of the gas? It's quite possible the problem is a faulty Idle Air Control (IAC) valve (sometimes also referred to as a throttle bypass valve). This valve allows air into your engine when the throttle plates are closed thus allowing the car to idle when you don't have you foot on the gas. When it gets dirty or "stuck" it stops letting air in and thus your car dies. Not to worry, this is an easy problem to fix and can be done in less than 30 minutes even by a novice. If you do decide to take on this procedure yourself please drop us a line and give us some
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Parts and Tools...
For this repair you'll need a new IAC valve (which comes with a new gasket) and a 10mm wrench or socket. Prices for the replacement part can vary from about $50 to $80 depending on where you shop (even more for OEM parts from the dealer). In our experience most of the aftermarket replacement parts are good quality parts and perform well.