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plug wires arcing. causing misfire?

  • Thread starter Thread starter 96GT281
  • Start date Start date Sep 1, 2008

96GT281

New Member
Apr 12, 2008
0
0
0
Stuart, Fl
Sep 1, 2008
#1
  • Sep 1, 2008
  • #1
the other night my car was missing bad under load. i did the plugs and it stopped. but now its doin it again but just a little. i moved all the plug wires away from anything metal an it stopped. could it just be because they're old
 

nyuk98gt

15 Year Member
Oct 10, 2000
1,427
6
79
Chesterfield, MO
Sep 1, 2008
#2
  • Sep 1, 2008
  • #2
96GT281:

Sure! If those are the original wires, it's past time to replace them, lol (although they do last a long time).

If you can see arcing then it's time to replace the wires. You can measure the resistance of each wire along with the physical length of each. Then you can compare "ohms/foot". If one is a lot higher than than the others then you know that wire is shot. The $20 Haynes manual (AutoZone sells 'em) has the acceptable range of resistance/length for the wires.

Pull each boot off (carefully -- you don't want to twist or bend the wires). Test fit using an old spark plug. The boots slide on the wires and it is common that the wire tip is too high in the boot (i.e.-- the boot slid down too far) and it is not "clicking" onto to the plug tip properly. You can slide the boot on the wire but move it only about 1/8" at a time. Hold the wire firmly and pull the boot down or push the boot up on the wire, as required. Take your time if you have to do this or you will break the conductor in the wire.

Last thing: pick up some dielectric grease (comes in little squeeze packets) and put a SMALL dab in the boot. Swish it around with a Q-Tip. It will keep moisture out and help to maintain good conductance.

Post back with an update. And watch out for TS Hannah!

Chris
 

98COBRA281

10 Year Member
Nov 24, 2007
1,348
30
59
Port St. Lucie, Florida
Sep 1, 2008
#3
  • Sep 1, 2008
  • #3
yeah last night we opened the hood and when we reved it you could see the plug wire arc spark to the t-stat housing, i wouldnt dought it there the original wires, the car didnt have any thing changed on it, it ever had the orignal brakes and fuel filter a 85k miles
 

96GT281

New Member
Apr 12, 2008
0
0
0
Stuart, Fl
Sep 1, 2008
#4
  • Sep 1, 2008
  • #4
i dont think that they are the original wires but yea my car had the original brakes and fuel filter
 
P

playboyroy

New Member
Aug 28, 2008
17
0
0
Sep 2, 2008
#5
  • Sep 2, 2008
  • #5
Shop just changed my orginal wires and plugs. a couple of plugs should arcing. Not bad for 10years for both plugs and wire.

went with 9mm ford racing wires $77 from summit and motorcraft plugs from local shop.
 

fudleyd

New Member
Jan 10, 2003
180
0
0
Littleton, CO
Sep 2, 2008
#6
  • Sep 2, 2008
  • #6
Worn out/damaged wires can definitely cause a misfire. I just had to replace the stockers in my gal's ride...
 
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