Yesterday my CEL came on out of the blue and the truck idled like crap and ran like crap. I used my OBDII reader and code P0306 came out. That explains the rough barky idle and accel. Cylinder 6 misfire.

My plugs were last changed Feb. 12, 2004 w/ 95,778 km's (59,513 Miles)

4 years and 116,000 km's (72,079 Miles) later.....I guess the plugs are in need of a change......I'll need new wires too, I never changed those, so they could very well be the originals.

Currently have 212,000 km's (131,730 miles) on the 2001.

I'll let you know what I find.

*UPDATE*

Removed the 6th cylinder plug and the 5th to compair the two. Both plugs were dirty looking but the 6th cyl plug is wet....Smells like fuel too.

Any input would be appreaciated. Would this be an injector issue, too much fuel into the cylinder, or a much larger issue?

 

sounds like its not firing, maybe the wire is bad. I had the same issue once and the wire that was replaced by the previous owner got burned by the exhuast manifold because he didnt route it like it should of been.

Caused the truck to run like crap and reak of unburned fuel.

 

I just ordered in some new plugs and wires. Even if that doesn't solve the problem, it's one less area of concern but either way, from what I seen on plugs #4, #5, and #6....they are in need of replacement. The wires are an unknow too, I've put over 138, 000 km's (85,750 miles) on those wires.

Hopefully (finger crossed) that solves the problem.

.....But by all means, keep the input coming on other possible diagnostics.

 

I had the exact same problem not but a month ago. New plugs and wires solved it and was cheap and easy to do myself

 

I didnt even have my 98 like a month before it did that. The previous owner really routed it different than it should of been lol.

That was 5 years ago lol.

 

Sounds that will more or less be my issue, just replace the plugs and wires.

I didn't want to go to the local auto parts store for plugs and wires, I've heard a lot of bad things about buying and installing the "cheap-run-of-the-mill" plugs and wires in the Rangers. I figured I've got this many miles off the Motorcraft, might as well stick with genuine Ford parts and hit up the dealership. The plugs are cheap to my suprise (under $5 each)........I just checked an old invoice from another Ford dealership and they charged me $8 a piece 4 years back.
The wires are under $60. They didn't have any wires in stock so I'll have those by Monday.

I'm keeping my fingers crossed that that is the problem.

Now I just have to test my luck getting the plugs out of the #'s 1, 2, and 3 hole. Better know as the fun side of the block. I read that the 4.0's are a PITA to get at those, so I'm hoping just taking off the wheel on the passenger side does it. The drivers side was easy, I removed all the plugs from up over the fender in the engine bay....that was the easy side I guess.

Thanks for the input guys!!

 

Just got everything this morning......will be changing them tonight after work.

Just some info for those curious.

Motorcraft wires: WR-5996 (1U2Z-12259-EA)

Motorcraft plugs: SP-432 (AGSF32FM)

 

So I replaced the plugs and wires today. From what I read on here, I thought the #1,2,3 plugs were suppose to be impossibe to remove and are just a PITA.

I found getting the wire holder tabs loose was the hard part.LOL

Took almost 2 hours to do, that included a trip to CT for a new spark plug gap coin.

So with the new plugs and wires, I still have a misfire in cylinder 6. Where do I move onto now?

 

I bit the bullet and replaced the coil pack. I found the Motorcrafts on the net for cheaper, but I needed it, so $100 from the dealership it was.

I swapped it out, cleared the CEL, and started the truck up............idles and runs like it should. So the issue was with the coil pack, but the plugs and wires really needed to be changed anyway. So $225 and 2 hrs of my time, my ignition system is brand new.