I seem to have a miss around idle -1800 rpm. I dont know if because of the cam or what. so today i pulled the plugs and #5 seems to be a lot darker than the others. Whats causing this? any advise please. thanks
Need spark plug advise
- Thread starter 93stang burden
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65ShelbyClone
Founding Member
Looks like it's rich on #5. Injector sticking, perhaps? You could try trading it with another cylinder to see if that's the problem. I would do a cylinder balance test first just to see what the computer says.
i"ll try to trade it out tomarrow. but these injectors are only 15 months old. what about the color of the other ones?
65ShelbyClone
Founding Member
They look typical to me also. Possibly that #5 plug is not firing all of the time. Possibly it is interfering with #6 since they are companion cylinders which fire consecutively. I'd make sure your number 5 & 6 wire are separated on opposite ends of the wire loom and only run perpendicular to each other away from one another. Cylinders 1 & 3 are like this also in the firing order. If the wires are ohmed out and good, switch plug 6 with say 7 or 8 or either 1, 2, 3, 4 and then see what it looks like. If either of those plugs get dark, then proceed to swapping the injectors. This way, its less work and may solve the problem easier ... afterall, new injectors really shouldn't be loading up the cylinder. It could happen but likely your problem is in the ignition system. Post what you find!
welli did the cylinder bank test and all came out fine. the ohms all seem to be close with differnert legnth plug wires and i did switch out the #5 and #8 plug so we will see what happens.
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