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Hi Everyone!
I am planning to replace the 8 Ignition Coils on my 2007 F150 XLT with 4.6L.
There are rails that run above the coils and I was wondering what they are and if they can stay in place while removing the coils?
Thanks in advance for your advice.
2007 F150 4.6L passenger side above the Ignition Coil
I am answering my own question. The COP devices (Coil Over Plug) are able to be removed without removing the rail above them. On my 2007 4.6L F150 I used a 7mm socket to loosen and remove the retaining bolt on the COP. A slight tug pulls the whole COP out of the well and off the spark plug.
I bought this truck new, and now it has about 110K miles on it.
About week ago, I noticed a shudder after the engine got to full temperature and while accelerating up an incline. Some folks in various Ford forums were calling this a light load misfire and for the most part, I was hoping that was all that was wrong.
I bought 8 new Motorcraft d508 COP units for about $166 on eBay and 8 new Motorcraft SP-493 spark plugs on Amazon. I started by replacing the spark plug and coil on Cylinder 5. That’s on the driver side at the front of the engine. Of course, that was the easy one. I was glad to learn that the 2007 4.6L F150 does not suffer the same sparkplug breaking as the 5.4L does.
When I removed the COP on cylinder 6, I was surprised when I looked down in the spark plug well and I could not see the nut on the spark plug. It pretty much looked like granola down there. When I applied a strong stream of air from my air compressor, a massive load of dirt, debris and water came flying out and after 3 or 4 applications of blasts of air, I could finally see the nut and the whole plug. The water did not appear to be coolant. I began to suspect that this might be where my misfire was happening. I replaced the COP and plugs on Cylinder 5, 6, 7 and 8 and took the truck out for a test drive. No more shudder and smooth as silk. Now for the passenger side and cylinder 1, 2, 3 and 4.
My truck is covered 24x7 and hasn’t been out in the rain for many years. It does get a rinse from the hose every now and then. So that water has been in there for a very long time. I guess it had nowhere to go even when it got very hot. It may have entered the engine compartment through a gap in a seal somewhere. I’ve seen several folks in the forums with some ideas that I may try. I am going use some dielectric grease where the COP sits on top of the engine.
I pretty much followed 88racing’s advice on the use of dielectric grease. I ordered some foam tip applicators for that purpose. Thank you 88racing!
Originally Posted by 88racing
You should only grease the inside of the boots, and maybe put some on the porcelain plug shell. Try to keep it off the actual contacts and definitely don't put it on the plug tips.
Dielectric application:
1. Grease the plugs ceramic before install. This assures proper seat. Without it, the COP boot may buckle.
2. Pull the boot, then give the spring a couple tugs to make sure the spring to coil blade connection is secure.
3. Grease the entire inside of boot to protect against moisture and to focus coil pulse to the spark plug. Without it, pulse jumps, etches and leaves carbon trails inside of boots. Boots become weak and can deform.
4. Install the boot over the spring and onto the coil. With a small screw driver or curved pic, pull the spring from the end of the boot approximately one half inch. Slide the screw driver across the spring, keeping it from recoiling back into the boot.
5. Clean grease from spring end with a grease cutting agent. Lacquer thinner or brake cleaner works best.
6. Release spring so that it recoils back into the spark plug boot.
7. With a small brush or finger, grease the top seam of the boot.
8. Install coil.
You can further protect using clear GE Silicone between the boot and cylinder head. That's more less an option, but it does work. ____
