1997 Ford Aerostar


I have a 1997 Ford Aerostar. The engine is shaking and popping. Its not constant, but its probably not safe to drive to far. We have done a tune up on it and changed the oil. also changed the coil pack. It did seem to improve, but its still not working properly. What do you think could be going on with this vehicle? Thank you for any assistant you can give me. Gina Mace