Has anyone besides me had Coil Packs die? I've got a 01 F250 CC long bed 4x4 with 36,300 mi. Bought it new, just don't drive it that much (since the two of us have four other vehicles). At 35,500 mi , under warranty, it started running rough at low RPM (1500-2000) in OD. Took it to dealer and #8 Coil had died.
This last week it has started again. Since it's out of warranty they want $100 to plug in their computer and less than 60 seconds later tell me which coil died. Maybe I'm tight or cheap ( I like to think I'm frugal), but I think $100 a minute is a bit salty. Does anyone know of a quick way to tell which one has quit? Ford want's $100 a piece for the Coil. Advance Auto has them for $54.
Thanks,
Tazman

 

Do what I did. Buy 2 of the 50 dollar items and replace the front 2 coils. Take it for a drive. If it runs fine problem solved. If it still runs lousy, take the 2 you just replaced and put those in place of the ones right behind the front 2. Repeat as required until the problem is solved. I did 2 coils at a time because I'm too lazy to climb under the hood potentially 10 times. You may also want to consider replacing the boots while you are under there. Cheap enough to do 6 bucks each.99 F-350 CC LB V10 Lariat 4x4 SRW

 

Good idea Wolf. I think while I'm at I'll check to see if I get a reading on my VOM on the front two. It would be nice if you could pull the lead off and see an open circuit going toward the plug. I'll let everyone know if this is a good test for bad coils. I'll have to wait for a little better weather, with a tall fiberglass shell on my truck, it won't fit inside.
Thanks,
Taz

 

If it's missing at idle....You can unplug the power lead to each coil untill you find the one that is dead.

 

I had the same problem but I was able to diagnose which cylinder was misfiring more easily. I have an actron cp9575 auto scanner that I picked up for less then 50 bucks. The scanner indicated an error code which told me that cylinder number four was misfiring. I replaced the COP which fixed the problem. I have used the scanner to correct other problems too which saved me time and money.

 

A vacuum leak can also cause rough idle . Check your PCV hoses and its plastic 90 degree elbow for any cracks.

Already good suggestions were made (like swapping a new coil ).

Unless your truck is an OBDII compliant (means built for CA or some other northeast green states) I doubt that you would get any misfire reading with any scanner (Check the sticker under hood see if it is OBDII or OBDI ).

In V-10 forum , most reports show that these COP coils easily last 100K+ miles .
I suggest you do some troubleshooting . Good luck.

 

P0304 Code - Cylinder #4 Misfire

 

10 year old thread, just got bumped.