Hi everyone. I bought a used 98 f150 and love it to death, however recently a surge went through my ignition system. At first I took it to a dealer who found the problem-an ignition coil burned out. This was replaced for a hefty $350, and it still was firing oddly. The dealer suggested to replace the EC Computer for another $400. Being on a budget, I replaced it myself. It's firing a little better, but I think the surge effected some plugs and wires causing it to miss. I have all the plugs, tools, and wires but I need to get my hands on a firing order diagram, just in case the dealer might have crossed a wire. I want to check this possibility out before I start replacing plugs and wires, cause it looks like a royal pain. Can anyone help out??
Alright, thanks to your diagram, I've determined that the coils for 5 and 3 are dead, The rest fire beautifully. funny thing is, this is the coil that was just replaced. Bad coil? I already replaced the ECC. So what controls the coils and tells them to fire besides the computer? any thoughts?
Electronic Integrated (EI) Ignition module is incorporated into the PCM.The PCM uses a signal from the camshaft sensor to determine piston position.Ignition timing is determined by the PCM,which then signals the module (PCM) to fire the coil.
Hey guys,I have an 1997 F-250 4x4..triton 5.4.check engine light just came on yesterday,truck seems to be running fine,had a code check done,it says my #2 cylinder is miss firing,,now,,lol where the heck are the plug and wires so i can see if any are loose??
All 5.4 engines and 2000+ 4.6 engines use a coil-on-plug system. Every spark plug has a small coil located on top of it. No spark plug wires in the old fashioned sense. Look throughout the spark plug replacement threads in the F150 and Expedition sections for illustrations of the plug location and other info that may be helpful to you.
Ok i'm back,,I just tried to change my plugs yesterday,,I did 7 in about 1 1/2 hrs.lol crazy,,ok now I cant for the life of me get to 1,,standing in front of truck looking at motor,it's the 3rd on right side,looks like I have to take of a vacum something,which looks likeits mounted on the fuel inj,,lines or some shiny set of tubes,,that are connected to the manifold in a few places,,now how the heck do I change it? shop wants $75. to do it,,ha ha ha ha
Did you get it figured out yet?
The #7 plug is a wee bit of a pain
I get at the screw that holds down the COP with a 7mm universal socket and an extension but you can probably do it with a nut driver instead. If you dont have a 7mm a 9/32 will usually work.
Once the COP is off you just use whatever combination of universal joints and extensions that works for you.
Some people remove the fuel rails to replace their plugs but I never do. It does make it easier to get at them but I dont like having stray fuel around and worrying about whether the injector O-rings will be ok etc.
And I'm lazy