P2646 - "A" ROCKER ARM ACTUATOR SYSTEM PERFORMANCE / STUCK OFF

In order for air to enter and exit the cylinders, a valve assembly must open and close in a synchronized manner, taking into account the position of the piston. To do this, the timing chain or belt is used, which causes the crankshaft to drive the camshafts to press the rocker arms. The rocker arms press the valves to open and allow the cylinder to enter or escape.

The swing arm control solenoid delivers hydraulic pressure to the variable timing mechanism. With this, the Variable Distribution System (VVT) can adjust the valve timing as needed. The Powertrain Control Module (PCM) uses the oil pressure switch on the swing arm to check that the oil pressure is right so that the VVT system is activated correctly. If the PCM does not detect the correct voltage signal on the switch, it will set the DTC code P2646 OBDII.

• The Check Engine light is illuminated.
• Loss of motor power.
• Higher fuel consumption.

The causes of the storage of the fault code P2646 OBD2 are

• The level of viscosity of the oil may not be adequate.
• Obstructions in the oil passages.
• The rocker arm actuator may be jammed due to elements sticking to it.

The steps to solve the problems associated with the diagnostic code P2646 OBDII are the following:

• Check that the oil level and pressure is the one required for a good operation of the Variable Distribution System. Besides, take into account that the viscosity of the oil has an important role in the operation of this system. Make the respective adjustments
• Check the oil lines for blockages or clogging.
• Check the cables or connectors related to the swing arm control solenoid. Correct problems such as worn or corroded cables.