97 5.0 w/ Cyl #4 misfire

[mf7365]

I've got a 97 mountaineer 5.0 w/ 134,000 mi. Maintenance has been by the book and oil changes ever 3-4k mi. I actually seafoamed on the last change along with replacing the PCV.
As I was driving today I noticed some hesitation and a shaking at idle. CEL came on and when I had the code read it came back as cylinder #4 misfire. Any ideas on what the problem could be and where or what to look for?

 

[techieman33]

The first step is to check the spark plug, and plug wire for any signs of damage, make sure all of the connections are good, etc.

 

[section525]

Then swap the coil packs and see if the cylinder # changes.

 

[mf7365]

At 128,000 I replaced the wires, plugs, and cam position sensor and cam synchronizer. I checked earlier, but will do another check. Also, what position is #4 looking at the truck from the front? I loaned my book out and am drawing a blank.

 

[section525]

Passenger feet.

 

[techieman33]

#4 is the back plug on the passenger side

 

[TheJackal]

I just had this problem myself. Wire was OK but it turned out to be the sparkplug. Be forewarned, if yours is like mine, it's a pain in the ass to get to the plug.

It should be able to go more than 6,000 miles but better to check to be sure before replacing more expensive stuff.

 

[techieman33]

I just had this problem myself. Wire was OK but it turned out to be the sparkplug. Be forewarned, if yours is like mine, it's a pain in the ass to get to the plug.

It should be able to go more than 6,000 miles but better to check to be sure before replacing more expensive stuff.

The plugs on the v8 are all pretty easy to get to if you take the fender skirt out.

 

[mf7365]

I just got the fender well off, and sure enough the #4 cylinder wire had come in contact with the exhaust manifold and burned right through. The question now is, how can I get a single wire for that cylinder or am I screwed and going to have to buy a brand new set? I just bought these 1 year ago (motorcraft oem)

 

[Dan Whitaker]

You are stuck buying the whole set.

 

[mf7365]

Well, my local dealer found me a single wire. They used to sell them individually, but the stock number came up as discontinued. He called around the country for me and found one still on the shelf in Kentucky. $26 plus shipping, but that beats $135 any day.

 

[Dan Whitaker]

You can get Motorcraft wires from several places for about half what the dealer ship sells them for.

 

[Turdle]

Oreilly sells the whole set for around 70 bux