Does anyone know what the problem / problems maybe in a 1994 continental w
3.8L. Just had the head gaskets replaced on this car. Heads cleaned up, new plugs, wires, and cap, rotor, fuel pump replaced. But the car does not idle smooth!Mechanic is scratching his head! Does not want to throw parts on it if does not fixed. He drove it on the highway up to 60 miles an hour and back down to 30 ( apparently to reset computer, but still idles rough. However driving around normally it runs great. Any ideas or is there something to be done to reset?
T.I.A.