one more thing to check is a leak at the carb base or at a gasket cauing a vacuum leak. you mention that the truck runs better shortly after spraying stuff down the carb, the spray may seal a vacuum leak for a short time.


1951 Chevy 3600, 1996 Yukon, 2000 Road King
It is easy to take liberty for granted, when you have never had it taken from you.
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