Random miss .Timing light same miss?
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Joined: Aug 2002
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From: CA
Random miss .Timing light same miss?
Also take a vacuum gauge reading at idle. You should see about 17 to 22 inches at idle. If you see between 12 and 16, and the engine seems to run steady other then the random miss, there's a good chance you do have a vacuum leak, and 60% of the time it's the intake gaskets, carb base gasket, or vacuum lines, while the rest of the time it's leaky intake valves. If you do get this lower reading, let the engine idle and take a can of NON-FLAMMABLE spray carb/choke cleaner and spray it lightly all around the intake to head joints, the carb base, and your vacuum lines. If at any point while you're spraying the engine speeds up a little bit, you've got a vacuum leak (unless it's valves). Remember that it could be a leak under the manifold where you can't spray. Even a small vacuum leak can screw up the fuel/air ratio and cause mis-firing. If it has no effect, re-read the ignition posts. Polkat.
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Joined: Dec 2001
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From: Louisville,Ky.
Random miss .Timing light same miss?
It sounds like a lean condition. Probably from inproper carb jetting. The preset idle mixture is probably lean too. Back out the mixture screw a turn or two and see if that doesn't help.
Jimmy
Jimmy
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