Help!!! engine misfires

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Dec 6, 2007 | 04:16 PM

flatline911

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Help!!! engine misfires

Hi Guys: Havent been around for a while but im here asking for your help.....My 2000 f350 developed a steady misfire at idle 230,000 miles v-8 5.4 gas motor....I changed the spark plugs to autolite dbl platnum @ .054 gap and found 1 coil all rusty and crudy last cylinder on the passenger side closest to the firewall (real bitch) anyway started the truck and misfire was gone ....to this point not once had the check engine light came on....drove for a while stopped the truck for about 30 mins. and when I started it up check engine light came on and I had a different missfire situation....now it steadly misses under acceleration.....ran engine code and it was P0354

Iginition Coil "D" primary or secondary circuit malfuntion

Can anyone help....I dont even know where coil "D" is thanks Gene

Dec 6, 2007 | 05:06 PM

BareBones

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From: Burnsville, MN

Its frequently mentioned that failing COP's will often work at idle yet stumble under load...

Dec 6, 2007 | 06:32 PM

flatline911

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What are COP's and will they say "Iginition Coil "D" primary or secondary circuit malfuntion " ?

Dec 6, 2007 | 06:59 PM

chuck06250

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COP= coil on plug

Dec 6, 2007 | 09:21 PM

BareBones

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From: Burnsville, MN

Cars/Trucks used to have a single ignition coil, whose output through the distributor had as many high voltage lines as there were cylinders. Now though the one ignition coil has been split into a smaller coil physically located at each of the cylinders, which apparently permits development of a hotter spark. So yes, a COP is an ignition coil, and quite possibly "D" means cylinder number 4, just guessing.

Hopefully someone who knows for sure can help us out...

Dec 7, 2007 | 01:52 AM

flatline911

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Thanks for the info guys....I have already replaced the bad coil that I found with a new one and it was cylinder #4 last plug on passenger side closest to the fire wall....I am suspecting something like you said because of what led to this misfire.....any tech guys know which coil is "D" ?

Dec 10, 2007 | 09:42 PM

flatline911

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Can someone post a pic out of the manuel for the firing order or tell me where to look to find a good manuel "Chiltons" doesnt have a very good one Thanks Gene