Ok, 07 expedition, 90k on the clock. Picked up an 0308 misfire this week and knew it was time to cbange the plugs.

I have 8 fresh motorcraft sp515s at the ready, the Lisle tool on standby and a full day to get it done.

I'm going to pull the COPs first, blow everything out, give them a 1/4 turn and soak them with pb blaster for a couple of hours. Hopefully...that will work.

Question is....should I go ahead and change all the COPs too while they're out. I can pick up 8 accel cops for $205...?

 

I would change coils as well. #8 misfire could very well be the coil itself and if they're already out, why not change them all. That way you don't have to change them out one at a time whenever they fail. Remember to put some dielectric grease in the boots to keep a good seal between the plug and the boot. Let us know how it turns out!

 

Good call. I went ahead and picked up 8 Accel coils while these were soaking.

So far so good. The #4, rear passe ger sid e, plug came right out once I cracked the seal - unbroken. It was so loose that I thought for sure it has broken. The plugs have been soaking for a couple of hours now - time to go start turning them.

 

Make sure to hold your tongue right!

 

Got it!!! All 8 out without breaking a plug. Anybody need a good deal on a Lisle tool - 65600?

Now to go pick up the COPs, install and button it all back up.

Will give details in a few of what I did

 

Did you have engine hot or ambient temp?

 

The truck was ambient temp - it sat overnite and was cool.

I started by running a tank of Techron thru last week.

This morning I started by pulling off the airbox and plastic cladding as well as removing all of the cops. This alone took an hour as the cops in the back, 4 & 8, are hard to get to.

I then cracked each of the plugs about 1/8th of a turn each and then sprayed a liberal dose of pb blaster in the head. I then left it alone for a couple of hours.

As noted earlier, the passenger side rear most cylinder, #4, was loose and came right out after cracking it open. I thought for sure it was broken but it was not. It had some pretty good chunks of carbon on the lower sleeve but they were free.

I went back after a couple of hours of the plugs soaking in pb blaster and then tested each of them with an easy 1/8th turn. They were tight as could be and a real booger to get started. I turned each plug one click of the ratchet at a time. Each one squeaked and squealed with each turn of the ratchet; nerve-wracking. I would turn 2 or 3 times and walk away for a minute and catch my breath.

After 10 or so clicks, I sprayed some carb cleaner down the head and let it soak for 10-15 min which further loosened up the varnish.

It took awhile, no kidding. Some came out pretty easy and others were pretty tight. Three out of eight should have broken as they were heavily coated in carbon - I was surprised they didn't when I pulled them out.

I vac'd out the head, lubed up the new plugs with anti-seize and reinstalled. I torqued each plug to 17lb/ft and reinstalled the new Accel COPs. She cranked and ran strong on my test drive. Very pleased.

Notes:
1) I used Motorcraft sp515 platinum plugs. I ordered them on ebay for $80 shipped - less than $10 per plug. My local autozone sells them for $13.
2) I removed all of the fuel injector and COP connectors and pushed them out of the way; the FI plugs are white/tan, COP plugs are black. I lubed them all with dilectric grease upon reinstall.
3) On the drivers side, I disconnected one of the fuel lines at the firewall that passes close to the #8 plug to give some more room. I also moved the crank case breather tube for more room to work. Both disconnect easily w/out any special tools.
4) On the pass side, I moved the big wire bundle out of the way that's attached to the fire wall with a clip. The heater hoses are a pain but they move freely.
5) I also picked up the Lisle 65600 tool on eBay in case I needed it, which I didn't. I'll look to resell it now that the plugs are coated with anti-seize.
7) Be patient. This took me most of the day today as I cleaned as I went and took extra time. It worked.
8) I used Accel coils - part# 140033. I could get 8 from Summit racing for $204, so I went to my local AutoZone and they matched the price at $25 apiece. Saved time and shipping.
9) All told, I spent $300 on plugs and coils; I figure I saved at least $500-600 from going to the dealer.

Let me know if you have any questions.

Accel coils in place and ready for another 90k!