Question about 1988 Ford F 250

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Idle my truck is failing smog because of somthing wrong with my idle controll when i step on the gas the idle will drop back down but not all the way it sticks at about 2500 rpms but if i step on the gas two or three times after it drops backdown to normal, any ideas?

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My first tihing I'd look at would be the cable disconnect it and see if the Idle now drop all the way down, If not see if the throttlebody linkage is need of lube.
Next turn it off take off the air intake hose Block the throttle wide open use some carb cleaner and a toothbrush to clean BOTH SIDES of the throttle plates in the throttle body and as far inside as you can shoot carb cleaner in and clean until those plates are sparkling BOTH SIDES OF THE PLATES INSIDE AND OUT re connect the hose UNBLOCK THE THROTTLE!!!!!!!! Start it it will start a bit hard but will run much better,
If this information is helpful please give me a fixya! rating
If you need any further help on this problem contact me in fixya or at

Thank you, Randy

Posted on Aug 19, 2008


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