I've been chasing a miss in my V10 for a while now. I "thought" that I had it worked out, it was running great, etc. Then while towing my travel trailer 600 miles from home the V10 started missing again, very noticeable while in OD.

To fix the "miss" before the trip with the camper I ended up replacing 4 of the coils with these yellow things called Accel Supercoils. Someone on this forum told me that they may fail within 1000 miles.. not sure if they are what brought the miss back but I don't want to run them any more.

I kept my Motocraft coils that were "bad" for some reason. I am kind of glad that I did.

I was doing more reading her on FTE and someone in the High Mileage thread mentioned that his/her V10 has over 300k on the original coils. He/she changes the coil boots and springs at 100k and then I read someone else say they clean off the brass mounts on the bottom of the coil (that the spring snaps into) and they use dielectric grease on everything.

Well, I didn't use dielectric grease, I didn't replace all the boots and springs, and I didn't clean off the spring mounts on the bottom of the coils.

I took out all the coils tonight and determined that I would be more through in my maintenance. I am going to disassemble the coils (just take the boots and springs off) and throughly clean everything.

I also took my 4 bad motocraft coils and look at what I found



It was completely corroded, this was the worse out of the 4 but they all had some corrosion of some kind, some white, some green. UGH... Well, thats probably part of the problem.

For a comparison, here is one of the accel coils where you can see the brass spring mount clearly.



So, How am I going to attack this issue?

I found these on ebay. New Boots and springs. Not too bad (8 of them) for $20.00 free shipping. I got 2 other new ones from the local parts store. So for about $30.00 I got new boots and springs for my Motocraft coils.



I am going to use some gun cleaning brass brushes (.22 cal) to clean the little springs mounts. I'm also going to use this



to clean the connections completely.

After that I am going to use this dielectric grease on every connection. (spring mount, boot, spark plug end of the spring.

Hopefully, this will resolve my miss.

Here is a pic of the 4 yellow things



The end goal is to prove the theory that gets thrown around a lot, that it's not the coils that actually go bad, its the springs and boots, I'm going to add to the the theory that the little spring mount gets corroded and must be cleaned off.

Oh.. and I want to save $400-600 on new coils. LOL

More to come, and sorry this is such a long opening post.

Jerem

 

I've got new COP's and also have a miss problem after they were on there a couple of years ago. I'm thinking that it may be a connection problem. Last shop I went to moved the coils instead of replacing them to see if the code would reset in the new location. It didn't. I wonder if you could somehow tighten up the connection and use CONDUCTIVE grease (like antisieze) to enhance the connection. Dielectric is good for corrosion in multi pin connectors, but if the object is to increase conductivity, it would seem to me a small amount of conductive grease might be better. Of course, you couldn't use so much that it would short out the 2 pins.

I've spent a 1/2 day at the shop on my last 2 vacations on this issue. I'm about ready to find an old 12 valve Dodge Cummins and say the heck with it.

 

Well i cleaned my coils up really good. The little spring mounts in the coils all look great now. I took the coils outside to put the new boots and springs on and I found this.



5 out of 6 of my "good" coils had similar cracks in the coil bodies.

I reinstalled them anyway just to see and the miss is still there.

Looks like I am replacing all 10 of my coils.

Oh well, it was worth a try.

Thanks!

 

Yeah, those cracks... well, suck

Back in the old days, ignition coils would be filled with oil to keep them cool - I suspect that COPs run pretty hot, and then expand and crack the casing. Moisture gets in, and it's a total loss. If you were really frugal, you could put some JB Weld on the crack, after heating the coils in the oven to 250 degrees for 20 minutes or so. That is, if they check out with an ohm meter BEFORE all that work.

Let us know how you make out!

 

How do I check the coils with an ohm meter?

 

I think the Ford service manual has the specs, but it might be better just to check if you have a good spark - Put the boot on it, put a plug in the boot, and ground the plug to something. Then pull the fuel pump fuse and crank the engine and see what kind of spark you have - nice and blue/white is what you're aiming for. If it's yellow/orange, that's not good, and the coil is probably already toast.