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Old 08-20-2007, 09:45 PM   #1
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Default Cylinder 3 misfire...

So... my car started idling rough last week. Now it's getting REALLY bad. I've hooked up the timing light to each lead and all of them are hitting perfect, except cylinder 3 which misses every 6-7th shot.

I've replaced the plugs (gap .044 na) and wires. Resistance on the coils is within .2 kohm of each other and within spec. Any thoughts on why only one cylinder on a wasted spark engine would decide not to burn?
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Old 08-20-2007, 09:48 PM   #2
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Bad injector?
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Old 08-20-2007, 10:17 PM   #3
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the misfire is visible with a timing light.... which means I'm not getting spark.

I plan to try to following later tonight after the car has cooled some.

1) Close the gap on the plugs down to .040, from .044.

2) Swap leads on the coil for cylinder 2/3 and see if the problem moves.
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Old 08-20-2007, 11:07 PM   #4
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So... I just checked and it's the damn coil pack.

When I swapped leads on the coil towers the problem changed cylinders. So apparently I'm going to HAVE to go COP now.
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Old 08-20-2007, 11:09 PM   #5
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Oh boohoo, that's about the best damn motivation for going COP i've seen.
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Old 08-20-2007, 11:10 PM   #6
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I vote 2 - it's happened to me more than once
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Old 08-21-2007, 09:44 AM   #7
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Try cleaning out the coil towers with a brass brush. I've seen a lot of them eaten out and dirty
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Old 08-21-2007, 02:55 PM   #8
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Quote:
Originally Posted by olderguy View Post
Try cleaning out the coil towers with a brass brush. I've seen a lot of them eaten out and dirty
damn dirty old man mode now huh bruce
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Old 08-21-2007, 03:59 PM   #9
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Quote:
Originally Posted by olderguy View Post
Try cleaning out the coil towers with a brass brush. I've seen a lot of them eaten out and dirty
I checked out the coil towers with a flashlight last night... they are nice and shiny inside. I always use a good dielectric grease on plug wires. That's probably part of the reason I can wash my engine without it running like poo afterwards
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