VTEC System
- The VTEC system changes the cam profile to correspond to engine speed. It maximizes torque at low engine speed and output at high engine speed. The low lift cam is used at low engine speeds, and the high lift cam is used at high engine speeds.
- Both intake valve side and exhaust valve side have primary and secondary rocker arms. These rocker arms are locked and separated to change the cam profile by switching the oil passages. A roller rocker is used to minimize mechanical friction.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
- The oil passages is switched by the rocker arm oil control valve. The rocker arm oil control valve is controlled by the rocker arm oil control solenoid. The rocker arm oil pressure switch detects VTEC system oil pressure and sends this information to the PCM.
TERMINAL DESCRIPTION
| ENGINE SPEED |
ROCKER ARM OIL CONTROL SOLENOID |
INTAKE and EXHAUST VALVE LIFT |
| LOW |
OFF |
LOW |
| HIGH |
ON |
HIGH |