Note Ocv for VVL system may also be referred to as camshaft timing oil control valve VVL or Variable Valve Lift VVL oil control valve

When engine is operating in low-to-medium-speed range, low-and-medium-speed camshaft lobes operate to move the valves by using needle roller and rocker arm on camshaft changeover mechanism. See Fig. 68 . The high-speed camshaft lobes also push downward on the rocker arm pad, but because rocker arm pad moves

2001 ENGINE PERFORMANCE Theory & Operation freely, this movement of high-speed camshaft lobes does not cause the rocker arm to move the valves. When engine coolant temperature is greater than 140°F (60°C) with engine speed greater than 6000 RPM, the ECM operates oil control valve for VVL system to allow oil pressure to be applied to the rocker arm pin. See Fig. 68 . When oil pressure is applied to rocker arm pin, rocker arm pin is pushed to the locked position. This prevents rocker arm pad from moving freely, this changes operation from low-and-medium-speed camshaft lobes to the high-speed camshaft lobes. This provides more valve lift for improved engine performance and fuel economy.

Oil control valve for VVT is an electrically controlled valve that receives oil pressure from the oil pump. See Fig. 69 . When engine is operating in low-to-medium-speed range, ECM operates oil control valve to move spool valve to open position. This allows oil pressure to drain instead of being applied to rocker arm pin for use of high-speed camshaft lobes. When engine coolant temperature is greater than 140°F (60°C) with engine speed greater than 6000 RPM, ECM operates oil control valve to move spool valve to the closed position. This allows oil pressure to be applied to rocker arm pin for use of the high-speed camshaft lobes. The ECM uses input signals for engine speed, intake air volume, throttle position and engine coolant temperature to determine operation of oil control valve for VVT. If a problem exists in the VVL system, a Diagnostic Trouble Code (DTC) may be stored in ECM. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article for retrieving of DTCs.

2001 ENGINE PERFORMANCE Theory & Operation

Toyota Engine Ocv
Fig. 68: Identifying Variable Valve Lift System Components (Celica 1.8L 2ZZ-GE) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2001 ENGINE PERFORMANCE Theory & Operation

Ocv Oil Control Valve Toyota

Fig. 69: Cross-Sectional View Of Oil Control Valve For Variable Valve Lift System (Celica 1.8L 2ZZ-GE)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Fig. 69: Cross-Sectional View Of Oil Control Valve For Variable Valve Lift System (Celica 1.8L 2ZZ-GE)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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Responses

  • mildred
    Where to buy ocv 2zz ge?
    7 years ago
  • Saku
    How to replace a Timing Oil Control Valve for corolla?
    4 years ago
  • madeline
    How to test oil control valve timing camshaft?
    4 years ago
  • erno
    How to position oil control valve?
    3 years ago

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