V-10 coil pack
Lead Driver
Joined: Sep 2003
Posts: 5,844
Likes: 6
From: Albuquerque
If your V10 has thrown a code...and you can pin-point the COP, then an easy way of telling if the COP is bad...is to switch it with a known good one. If the trouble code follows the cylinder, then you know the COP is bad.
You could always try this tool...
http://www.waekon.com/ps/cop/copintro.html
Good luck...
biz
You could always try this tool...
http://www.waekon.com/ps/cop/copintro.html
Good luck...
biz
Elder User
Joined: May 2004
Posts: 936
Likes: 1
If it has a check engine light it will be easy to pull the code with any scanner. If there is no check engine light there is a computer a shop can hook to your truck and see which coil is faulty.
I there is a tool to check the COP off the truck, but you could just try a new COP in the bad one's spot.
Does the truck "miss" while under heavy load ie low rpm lugging? This is where a bad COP is the most detectable.
I there is a tool to check the COP off the truck, but you could just try a new COP in the bad one's spot.
Does the truck "miss" while under heavy load ie low rpm lugging? This is where a bad COP is the most detectable.
Frmr Ford Trans Engr
Joined: Aug 1999
Posts: 24,739
Likes: 2,669
From: SE Florida
Mine had a random miss. It didn't light the check engine light. It turrned out to be a couple of the boots between the coil and spark plug. All 10 of the coils were good and are still on the truck.
Elder User
Joined: Jan 2002
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Testing COP
A few months back I thought that I had a bad coil on my 2000 F350 V10, but it turned out to be a plug instead.
Last week the 4.6 in my Town car started acting the same way. Scanner indicated that #8 was misfiring and the MIL (service engine soon light was on). I did not want to buy a coil if I didn't have to, so I decided to test it. I used a known good spark plug that I gaped to match the Town Car spec (52-56). I used a heavy cable (Battery cable) and hooked one end to the engine block and the other end to the base of the spark plug. I disabled the fuel pump relay and pluged the boot onto the spark plug with the cop attached. Placing it so that it did not touch anything, I then turned the engine over. I could see that the cop was only firing intermittenly. Maybe once every 20 to 30 RPM. I removed the boot from the coil and inspected the terminals. The large copper terminal that connects to the spring inside the boot had turned green with corrosion. I cleaned it good with my knife and a wire brush, sprayed electrical contact cleaner on it and blew it out with compressed air. It is a lot easier to do than it is to describe. Anyway, it now works fine and no coil purchase was necessary. Good luck with yours.
Last week the 4.6 in my Town car started acting the same way. Scanner indicated that #8 was misfiring and the MIL (service engine soon light was on). I did not want to buy a coil if I didn't have to, so I decided to test it. I used a known good spark plug that I gaped to match the Town Car spec (52-56). I used a heavy cable (Battery cable) and hooked one end to the engine block and the other end to the base of the spark plug. I disabled the fuel pump relay and pluged the boot onto the spark plug with the cop attached. Placing it so that it did not touch anything, I then turned the engine over. I could see that the cop was only firing intermittenly. Maybe once every 20 to 30 RPM. I removed the boot from the coil and inspected the terminals. The large copper terminal that connects to the spring inside the boot had turned green with corrosion. I cleaned it good with my knife and a wire brush, sprayed electrical contact cleaner on it and blew it out with compressed air. It is a lot easier to do than it is to describe. Anyway, it now works fine and no coil purchase was necessary. Good luck with yours.
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Must it with H2O bottle
Proof way to tell if you have a bad boot on a good coil is to wait till dark, open the hood with it running. And get a spray bottle and put it on
"Mist" spray everywhere under the hood and if a boot is bad, you'll see a lightening storm , the spark always will take the path of least resistance and the must in their give it. Just that..... If you notice, with a bad boot, it also developed a miss when it's raining outside but goes away when it's not. Moisture in the
Air ays havoc on bad or broken wires/ plug boots, or any insulated electrical that suffers from intermittent problems.
Hope this helps,it helps me every time to find bad if wires or boots on these fords.
Mike
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Joined: Sep 2000
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From: Stephensville WI
Or another method.....
In the example DavidB provided in post #7, he knew #8 was misfiring, but didn't know what was causing the misfire. So, what you can do is swap the COP/Boot with another one, say out of cylinder #7. Swap the spark plug with #6. Clear codes and retest.
Now, the problem should have followed the bad part.
If #7 has a misfire, the COP/Boot is the issue.
If #6 now has a misfire, then the plug is at fault.
If #8 still has a misfire then the cause is probably not ignition related and you should start look at your injector or maybe a vacuum leak along the #8 intake port path, or worse yet a mechanical issue with cylinder #8.
In the example DavidB provided in post #7, he knew #8 was misfiring, but didn't know what was causing the misfire. So, what you can do is swap the COP/Boot with another one, say out of cylinder #7. Swap the spark plug with #6. Clear codes and retest.
Now, the problem should have followed the bad part.
If #7 has a misfire, the COP/Boot is the issue.
If #6 now has a misfire, then the plug is at fault.
If #8 still has a misfire then the cause is probably not ignition related and you should start look at your injector or maybe a vacuum leak along the #8 intake port path, or worse yet a mechanical issue with cylinder #8.
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