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.
Clock Spring Inspection [Standard 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 ...
Heated Oxygen Sensor (HO2 S) Inspection
HO2S Inspection
1. Connect the M-MDS to the DLC?2.
2. Switch the ignition ON (engine on).
3. Warm up the engine to normal operating temperature.
4. Access the following PIDs using the M-MDS..
VSS (Vehicle speed)
RPM (Engine speed)
O2S12 (HO2S output voltage)
5. D ...
Front Drive Shaft (Double Offset Joint) Disassembly/Assembly
1. Disassemble in the order indicated in the table.
2. Assemble in the reverse order of disassembly.
1
Boot band (transaxle side)
(See FRONT DRIVE SHAFT (TRIPOD JOINT) DISASSEMBLY/ASSEMBLY.)
2
Clip
(See Clip Disassembly Note.)
...