Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Air Flow System


Intake air from the air cleaner is metered at the air flow meter, flows through the throttle chamber and into the intake manifold, then flows through each intake manifold branch into the cylinder. Air flow is controlled by the throttle valve located in the throttle chamber. During idling, the throttle valve is almost closed and the air is fed through the bypass port mounted to the throttle chamber. The quantity of suction air is adjusted by the idle speed adjusting screw. During warm-up, the air flow is bypassed through the air regulator to increase engine RPM.