Thread: Idle up an down

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What will cause the engine Idle high one day low the next? Can't seem to get it adjusted.

Sounds like a vacuum leak to me

Could also be worn-out throttle linkage that rests at first one place and then another. Check also for kinking or binding in the linkage. Occasionally, someone will really crank down on the hold down bolts between the housing and the intake manifold and warp the housing, causing the throttle shaft to bind up or come free depending on the temp of the motor.

Rusty, stuck mechanical advance in distributr---------

Fuel pressure. Monitor at 4 3/4 to 5 lbs at the carb inlet. Excessive fuel pressure can hold the needle up off its seat and allow the fuel pump to blow raw fuel into the intake manifold, creating a tuning problem.
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