trouble shooting with misbehaving cyl.

[dale914]

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[NHVmaxpower]

Sounds like a wire or coil arching out.

 

[dale914]

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[dale914]

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[NHVmaxpower]

as an update, I pulled the plug, it looked the same as the kitty corner plug (right front) swapped plugs, same condition, I even had the plugged in another plug with it hanging out and ran the engine to see if I could see a spark, and I could not (granted, it was very light outside, so would that make a difference?) I'm thinking that I first need to replace the wires

When you swaped plugs did the good running cylinder start running bad? If it did I'd say replace plugs. If no change I'd look at coils,wires.

 

[mattmullins]

I would say carburetor problem because at above the boost it runs better because it's getting the carburetor from the other cylinder. probably not getting gas in the carburetor in the cylinder thats not running good

 

[wildweasel_pt]

WHen you say that it runs rough does it really run rough or is it just the noise? How is your exhaust? Are you sure you don't have a leak on that header?

 

[dale914]

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[dale914]

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[Rhoy Carter]

New plug wires can do wonders sometimes

 

[dale914]

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[44boyd]

Whens the last time you did a carb sync?

 

[wildweasel_pt]

iF its detonating you are lean. Check your plugs to see if they are grey or white on the electrode... Compare the plugs color wise. You are looking for a tan color, no white neither blackened (rich). Best thing is to get a O2 sniffer and check it out.

 

[jfeagins]

While you have your seat off changing out the bad wires, put a volt meter on it and test your idle voltage. Low voltage will cause weak spark too. The TCI boxes on our Vmaxes are touchy when it comes to enough voltage.

The idle circuits in the carbs are also notorious for becoming plugged up and causing poor idle and/or low & midrange acceleration problems.

If it's detonating, you could also have some really chitty gasoline in there. If possible, fill with a non-ethynol blend, and move up a grade to see if it improves on anything.

 

[mattmullins]

I would check to make sure each float bowl is getting fuel then if the spark plugs haven't been replaced in a while to replace them that's the cheapest way to start. but you said it went to the boost opens up it smooths out , and when the boost opens up your getting two carburetors per cylinder instead of 1 that's why I think that maybe you're not getting fuel . because when the vboost opens up you start getting feel from the other carburetor so maybe that's what it smooths out. plus check and make sure you're getting goods park we may need new coils

 

[dale914]

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[dale914]

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