2003 F150 2wd, 4.2L V6: Second cylinder is misfiring. I changed the spark plug and checked the wires, but problem persists. Does anyone have any advice? I read in the Chilton manual that you can check the coil pack pairs with a ohmmeter. I did and pairs 1/5 and 3/4 read the exact same resistance, but 2/6 was slighty lower in reading. Could the coil pack be the problem (just asking before I spend the $60.00)?

 

Take your coil pak to Autozone and have them check it. If its ok swap a injector to see if the misfire moves.

 

Would you explain to me how to change a injector (please)?

 

Hey, well I had a missfire in cyl 7, and it turned out it was just a bad wire. I read that you 'checked' the wire, what do you mean? Have you checked it with an ohm meter? If not, try that. In your repair manual it should tell you how much resistance per lenght of wire. It might be as simple of a fix as changing that wire out. Good luck.

 

You have to take the fuel rail out on the #2 Cyl side before you can get the injector out. You will need a special tool to release the fuel rail coupling, you can purchase one from autozone. from there the injector pops right out. I would stick with the coil first though, they are very common for going bad. I have replaced my #3 cyl coil. Autozone has a reasonable price on them 28-30 bucks or so. Last time i checked the Dealer price was triple that.

 

I had an intermittent miss at 84k in my V6. New plugs and wires didn't fix it, a new coil pack did.

 

thanks everyone...turns out it was the coil pack (crack on the backside even thought the primary and secondary resistance checks were all in range).