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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Idle Air Control Valve (M112)



The Idle Air Control Valve (M112) controls the idle speed of the engine by moving the plunger a set distance, known as a step. Fully open is zero steps and fully closed is 180 steps. The motor moves each step by sequentially changing the polarity to each of the two coils.