Engine dies at Idle



On two occasions now, I’ve come back to my car after stopping for maybe 10 minutes to find that I could start the engine, but it wouldn’t stay at idle without me holding down the throttle. So long as I kept the gas going, the car would keep running, but it would die if I let up on the gas. I could drive by slipping the tranny into neutral at stop lights, then engaging for travel. This kept up for maybe 10 minutes, then went away spontaneously.

The first time it happened, I had just gassed up with E85, and I thought I got water into the tank that had to be pumped through the engine to get to purer fuel. The second time, all I did was stop at a mall for 15 minutes.

2003 Ford Taurus w/ 112,000 miles


I’m assuming your Taurus is Flex-Fuel vehicle? If not, stop using E85 as a fuel.

You’re discribing what happens when a Idle Air Control valve starts acting up. This is a common failure on Fords. This valve is what allows air into the engine anytime the gas pedal is released so the engine can idle. Sometimes these valves get lazy where they fail to allow air into the engine for the idle condition, and the engine stalls. One of the indications that there’s a problem with this valve is, you can prevent the engine from stalling by slightly stepping on the gas pedal. This takes the engine off idle so the valve is no longer required to keep the engine running.



Yes, the Taurus is a Flex-Fuel.

Is there an easy fix on freeing up the Idle Air Control valve, like spraying WD-40 to lubricate the pivot pins?


Don’t use WD-40. But you can clean these. You’d need to pull it off and spray it out with something like a throttle body cleaner. This is not a very difficult thing to do. The hardest part might be finding a new gasket, but you can easily cut one from a sheet of gasket material (just ask at an auto parts store when you get TB cleaner). You should also take some electronics cleaner and then dialectric grease to the electrical connection.


Check the price of a new one. You might be surprised and find it inexpensive. We can hope. It will probably get worse as time goes on, It is typically intermittent at first and more susceptible when cold. Eventually, you will be driving with two feet if you have an automatic and three if you have a clutch.


I believe Autozone carried these for around $2. On the Vulcan, the IAC valve is extraordinarily easy to remove. Its held on by just two bolts at low torque, and connected by a plug.

Cleaning with throttle body cleaner may well work - it helped mine when it got sticky a few years back. I eventually replaced it, though, as I was tired of cleaning it. IIRC, you could get one for $60 aftermarket, ~$90 from Ford, or $6 from the junkyard.