Old problem not really solved
Lead Driver
Joined: Nov 2013
Posts: 7,178
Likes: 1,174
+1 on this idea. I had the same thought, including trying a different brand.
Lead Driver
Joined: Nov 2013
Posts: 7,178
Likes: 1,174
Just curious, do you have a troubleshooting guide saying to take the measurement with the key on but engine off? I'm not following how that value would mean much of anything. I'd think the voltage with the engine running would be more important.
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Laughing Gas
Joined: Aug 2010
Posts: 983
Likes: 49
From: Northern Kentucky
Jim: Coil (+) voltage KOEO = 6.77. Coil (-) voltage = 1.70 Coil (+) to Coil (-) = 5.0v.
Kr: (OK if I call you by your first initials
) I was checking KOEO based on what I saw on the forum. When it comes to electrical troubleshooting I am as dumb as a box of rocks.
All: I think I will pick up a set of Motorcraft copper plugs and a new set of wires also. Any recommendations on good quality wires?
Kr: (OK if I call you by your first initials
) I was checking KOEO based on what I saw on the forum. When it comes to electrical troubleshooting I am as dumb as a box of rocks. All: I think I will pick up a set of Motorcraft copper plugs and a new set of wires also. Any recommendations on good quality wires?
Cargo Master
Joined: Mar 2008
Posts: 2,573
Likes: 207
From: Washington
I would just swap out the plugs and save the wires for the next round.
Jim
FTE Legend
Joined: Nov 2015
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From: Angier, NC
I know it is easy to do both as you are in there but when tracking down issues it is best to do 1/one change at a time. That is 101 of testing
This way if something works or does not work or gets worst you know just what you did to make that change.
If you do both plugs & wires and say it gets worst what one caused the "worst"? If you did just plugs and it got worst you can throw the old plugs back in, test to see if you are back to what it was before the plug change then do the wires and test again.
Dave ----
FTE Legend
Joined: Nov 2015
Posts: 30,935
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From: Angier, NC
When you pull the plugs for swapping tell us or better yet take a picture of the ends to see if running lean, rich or just right.
I know it has been said you should not be lean with the PV and all but.........
Dave ----
I know it has been said you should not be lean with the PV and all but.........
Dave ----
Lead Driver
Joined: Nov 2013
Posts: 7,178
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Even better, duplicate the rough running and shut down the engine right away. Don't even bring it back to idle, if possible. That way the plugs will hopefully give a hint about why the engine was misbehaving.
FTE Legend
Joined: Nov 2015
Posts: 30,935
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From: Angier, NC
You are trying to get a look at the plugs when the issue happens.
Dave ----
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Lead Driver
Joined: Nov 2013
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My GB meter says 6.3 VDC
Just for giggles, my Fluke says 6.44 VDC.
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Laughing Gas
Joined: Aug 2010
Posts: 983
Likes: 49
From: Northern Kentucky
Thank you, sir, you are a gentleman and a scholar. My reading is 6.75 so the problem must not be voltage at the coil.
I have ordered a new set of wires from Rockauto (mine were older than I thought) and picked up a set of Motorcraft plugs so we will see where that goes.
I have ordered a new set of wires from Rockauto (mine were older than I thought) and picked up a set of Motorcraft plugs so we will see where that goes.
FTE Legend
Joined: Nov 2015
Posts: 30,935
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From: Angier, NC
Also if you find you are burning out coils, spark going from center to small neg stud that is a sign of high resistance on the high voltage side and the spark looking for the easy path to ground. Most of the time the cause is the wires but do not over look cap/rotor & plugs.
Dave ----
Lead Driver
Joined: Nov 2013
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All seriousness aside, did you try duplicating the rough running while spraying down the plug wires? Just because you didn't get the light show, that doesn't mean the wires are confirmed good. It only means they didn't fail a particular test.
Also, does your coil have the stock radio noise suppression filter? This is a small capacitor on the side of the coil. The lead is connected to the coil's (+) post. If shorted, it could cause ignition problems. It's okay to disconnect it, as it's only there to limit AM radio interference.