Fuel and Emissions System Description - VTEC System

VTEC System


At engine start, and high load


At cruise

The rocker arm oil control valve switches oil pressure to the oil passage in the intake rocker arm shaft. Oil pressure then enters secondary rocker arm A, and it moves the VTEC switching piston in the rocker arm.
This causes the VTEC switching piston to slide into secondary rocker arm B, locking secondary rocker arms A and B together.