Toyota 13523-22020 Gear Or Sprocket, Camshaft Timing

WT system is used on all models adjusting the intake camshaft timing by routing oil pressure to the intake camshaft sprocket/actuator assembly; it improves engine power, fuel efficiency, and emissions in certain circumstances. Some of these are; PCM which is the Powertrain Control Module, WT oil control valve also known as OCV, OCV filter of the oil control valve, and the intake camshaft sprocket actuator assembly. The PCM triggers the oil control valve that manages the flow of oil pressure serving to either protract or precede the camshaft. As it can be seen, the actuator assembly includes an inner hub that has fixed vanes which, when contracted by oil pressure, rotates the camshaft: altering the degree of inclination up to 21. In this case, the camshaft timing is adjusted depending on the current engine loads in order to enhance the efficiency and power. Maintenance must be frequent since problems stem from the oil control valve and the filter, to determine blockage and the extent of control. Also, one should check the functionality of the oil control valve plunger, which must move when voltage is supplied. Any comprehensive examination requires the removal of the valve cover and intake camshaft; in this case, the actuator assembly should turn freely using air pressure. If any of the components do not function as planned, then replacements are made and the reassembly is as follows: the reverse approach to disassembly.

The VVT system used in all models include an intake camshaft timing that is controlled by oil pressure to either advance or retard the intake camshaft sprocket/actuator assembly for improvement of the engine power output, fuel economy, and reduction of emissions where these conditions prevail. They include the PCM, VVT oil control valve, the filter for the VVT oil control valve and the intake camshaft sprocket/actuator. Using a number of sensors, the PCM decides the oil control Valve to regulate the pressure of the oil to the actuator assembly. The actuator hydraulically driven contains an inner hub equipped with the fixed vanes and through the oil pressure the rotation of the camshaft is performed related to the adjustment through which the camshaft can be in advance to 21 degrees, or in case necessary-to be in a neutral state. Dependent on the load on the engine, the system can control the cam shaft timing in order to provide the right combustion. Especially, VVT oil control valve and the filter should be frequently maintained due to most problems root cause from them. To diagnose, the strainer of the oil control valve filter should be free from blockage, the valve's resistance would then be evaluated; if this has exceeded the allowable limit then it must be replaced. The second examination entails observing the movement of the plunger of the oil control valve every time voltage is supplied. As for the camshaft sprocket/actuator assembly, the valve cover and the camshaft have to be taken off; the actuator is then cleaned and it has to be installed correctly with the functionality as well. It is recommended to test the rotation of the actuator using air pressure and if it fails to do so, one must replace the assembly. Disassembly is the process of taking apart the equipment while reassembly is done systematically in a backward way to the process of disassembly.

Some of the steps involved in the removal procedure include disconnecting the negative battery terminal, removing the drivebelt and alternator, taking off the valve cover and ABS actuator (if applicable), and more.

Supporting the engine is necessary to prevent it from moving or shifting while other components are being removed.

Disconnect the cable from the negative battery terminal.

Apply 14 psi of air pressure to the advance side oil port and attempt to rotate the actuator assembly by hand. It should rotate approximately 30 degrees counterclockwise from the locked position without binding.

Positioning the number one cylinder at Top Dead Center (TDC) is important because it sets the engine in the correct position for timing belt removal and installation.

Supporting the engine is necessary to prevent it from moving or shifting while other components are being removed.