Purpose, Function
The hydraulic variable valve timing actuator operates according to the hydraulic pressure and changes the phases of the exhaust camshaft. As a result, the open/close period of the exhaust valve is changed, optimized valve timing in accordance with driving conditions is realized, and the output and combustion efficiency is improved.
Construction
The hydraulic variable valve timing actuator is installed to the exhaust camshaft.
The hydraulic variable valve timing actuator has an assist spring to move the rotor in the advance direction while the engine is stopped.
Operation
At engine start
Because the stopper pin in the hydraulic variable valve timing actuator is engaged with the rotor at the maximum advance position by the spring force, the camshaft sprocket and camshaft are rotated as a single unit.
Retarding valve timing
Engine oil is lead to the retard oil passage by the OCV to apply oil pressure to the stopper pin and retard chamber. As a result, the engagement of the stopper pin is released, the rotor connected to the camshaft rotates in the retard direction against the camshaft sprocket driven by the crankshaft, and the valve timing is retarded.
Advancing valve timing
Engine oil is lead to the advance oil passage by the OCV to apply oil pressure to the advance chamber. As a result, the rotor connected to the camshaft rotates in the advance direction against the camshaft sprocket driven by the crankshaft, and the valve timing is advanced.
Maintaining intermediate valve timing
The retard and advance oil passages is closed by the OCV. As a result, the relative angle of the rotor and camshaft sprocket is maintained at a constant to hold the valve timing.
Hydraulic Variable Valve Timing Actuator Inspection
MechanicalAmbient Temperature Sensor [Manual Air Conditioner]
Purpose
The ambient temperature sensor detects the ambient temperature.
Function
The ambient temperature sensor converts the detected temperature to an electric
signal.
Construction
A thermistor-type ambient temperature sensor has been adopted.
The ambient ...
Clock Spring Inspection [Two Step Deployment Control System]
1. Disconnect the negative battery cable and wait for 1 min or more..
2. Remove the driver?side air bag module..
3. Remove the steering wheel..
4. Remove the column cover..
5. Remove the clock spring..
6. Verify that the continuity is as indicated in the table.
If not as indicated ...
Procedure [Plastic Body Parts]
Repair of polypropylene bumpers having damage that has reached the surface of
the polypropylene and are too serious to be restored by painting only.
1. Cut the rough edges around the damage with a knife to make it smooth. Sand
the area with a sander to make an angle of about 45°.
2. ...