I have a 97 4.0 SE with 164000 that I saved from the scrap yard here a few years back and due to not being able to get the title until last week I am just now starting to work on it. As of right now I have replaced the battery, pulled the in tank fuel pump and drained all fuel, installed new fuel pump, replaced plugs and wires. I am getting good spark to all plugs but from the moment I start it it has had a bad misfire. standing behind it sounds like it has atleast one cyl not doing anything. I put the code reader on and it came up with 02 sensor and 3 misfires, cyl 2 7 and I don't remember the other. On cyl 2 while running I can pull the spark plug boot off and it doesn't change how the engine runs at all. I have done that with all the plugs on passenger side and all but cyl 2 make a notable difference. haven't done to drivers side yet. I checked the resistance on all 8 injectors and all were within .2 of each other. If I remember right they were all between 16.3-16.5ish. I know that doesn't mean that they aren't plugged up. I plan on doing a compression test here probably this weekend. I went to do it yesterday but when I lent it out I didn't get any of my adapters back with it. after that possibly pull the valve covers to throw a dial indicator on the rockers to check and make sure the cam isn't worn out. Any help on what steps or suggestions I should do would be much appreciated. I am very mechanically incline with plenty of schooling in everything from large refrigeration systems to diesel engines all in marine industry though.