Ford Repair Questions? Ask a Mechanic for Answers ASAP
Start with checking for any vacuum leaks or any problems with the air inlet ducting being loose or damaged. Also be sure the air filter housing is sealed properly and that the air filter is the correct one. If no problems are found with the air filter or air inlet, check the throttle body for excessive build up of carbon or soot. If you can see carbon inside the throttle body (you will need to push the throttle plate open by hand to see inside) then the first thing to do would be a good throttle body cleaning.
This will usually take care of it, but if the throttle is too gummed up and you can't get it to come clean then you may need to replace the throttle body.
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