I have an 01 durango 4X4 with the 4.7L that keeps sending a code to a handheld reader that says cylinder #7 misfire. To me that is plugs are bad change them right? OK did that light came on again,went to different reader that said same thing. I changed the coil,like most would do next following chain of order.15 minutes later engine lght again!!!! Ok mind says stop for the evening have a drink to cool off from frustration like most. Next day take it to a third reader same reading,cylinder #7 misfire. Bought new fuel injector just as Hayes book said and changed it.Light on again.Same reading! now the motor is ticking like a time clockright above #7. Book has no morehelp and I am at a lose.Someone out there please help! Sad part is I am dis-abled talking my wife through the whole process as I watch and insrtuct(hard Enough). She is learnig really well guys so give a women a chance.Sorry but please help an injured firefighter and his wife,

 

you may have a broken spring, valve keeper, rocker arm, or some othe unimaginable problem in the valve train for cyl, number 7. so you will have to pull the valve cover, and inspect that area for damage. please after you pull the cover let me know what you find.

 

What plugs are you replacing them with?

 

^ what he said. Also how did the plug look that came out of #7 (and the rest) and do you still have them. If you do take a pic and post them. Plugs can tell you a lot about what is wrong.