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Discussion Starter · #1 ·
Changing a standard air filter today to a K&N and looking at the airbox under the air filter I see the the preheat tube is half missing and wonder how the system works? I would think that the "door" for the cold (protected) air inlet from the inner fender is thermostatically controlled by the warm (hot) air from the exhaust manifold (area) and opens at some point? But what if the tube that feeds the warm exhaust air is missing, deteriorated or not connect? I would think, if this is actually the way the system works(?), that the cold, protected air from the inner fender would never enter the airbox??? It has me stumped to the point I'm thinking of aircraft safety wiring or even zip tying the cold air access door open and blocking the passageway tube from the warm air inlet (red arrows). Does the system work without the preheat tube??

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