My station wagon won’t idle

October 1, 2010 | By Richard Prince

Question:

I have a 1990 Ford LTD Crown Victoria eight-passenger station wagon with the 5.0 Liter (302) V-8 Engine. I received this vehicle in excellent condition and have been restoring the exterior back to the factory items. I replaced the oversized tires, installed 15” chrome “smoothie” wheels, have had it detailed, and I had some body damage professionally repaired.

This vehicle always started when required but now it will no longer idle. I have been told that this engine had a plate installed (a mass air flow plate?) to control the idle. I have had this vehicle to my local mechanic, and he advised me of such a plate, but has been unable to locate one since Ford stopped making this item after a few years, and now that the vehicle is 20 years old, Ford does not make nor carry this plate.

Can you recommend a cure for this lack of idling, as it has almost caused some accidents, especially when pulling into a parking lot, gas station, or something like that. I have actually been coasting as the engine stopped running.

I need help in this matter as I will be driving this vehicle every day once I get all of the additions, detailing, etc. completed. Can you help or even tell me where I can locate this idle plate?

Answer:

I think that an idle air control valve controls the engine idle in your 1990 5.0liter engine. The failure of the engine to idle is likely the result of this valve’s failure. You can buy an aftermarket idle air adjustment plate from various sources, but this will not solve your problem if the idle air control valve is bad.

People usually utilize the idle air adjustment plate in conjunction with other aftermarket parts to solve problems that they create. For example, some have successfully cured the whistling noise that sometimes comes with high-performance throttle bodies and others have installed a plate to help control the idle after installing a high-performance camshaft. New idle air control valves are readily available for your car. The Motorcraft part number is CX1823.