I have a 03 Liberty V6 3.7L and When I got it it had a Misfire on Cylinder 4.I just thought it needed a spark plug change no big deal it ran great.I changed all spark plugs and the Check Engine light went off and it ran like a dream.About a day and half later the light came back on.It now had a shake to it so I went out and got a replacement coil and put it in did not go away and the Light started blinking.Went to go put it into a garage to work on it with a friend and smelt something burning looked under the hood and the coil pack was melted in half I figured it might have been a faulty coil pack so I put the old one back in to get to the house and by the time I got there it had already started melting this coil pack.I checked the spark plug to see if it was fouled and it looks like it did when i put it in.I do not know what to do at this point as I dont have the money to put it in a shop and dont know alot about engine work has anyone else had this problem?Ive read alot about these engines breaking valve springs?