Hello friend, you must check the ignition time, on the Sigual pulley it brings some marcara grooves, and attached to the engine there is a scale that scale brings degrees or numbers of the O at 20 it seems to me Ke if, where I am in Huejutla we put it at 10 degrees, with this 10 degrees the car works well, it does not take long to start, it starts to the yavaso and stops belling. You must consult your mechanic to keep the time or lamp it if it is said. And from the other way it is accelerated can only be your IAC valve, in the Ford brand cars can be washed, you just go back in tune to what the dirt comes out and then you put it, and if it continues so it does not use your iac valve and you must change it.