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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Intake Manifold Tuning (IMT) System

Intake Manifold Tuning (IMT) System




Engine power is optimized by closing and opening the intake manifold tuning (IMT) valve. When the valve is closed, there is high torque at low engine speed. When the valve is open, there is high torque at high engine speed.