How to fix P2646 Code: "A" Rocker Arm Actuator Control System Performance/Stuck Off (Bank 1)
A P2646 code is set when the computer (ECM/PCM) does not receive the correct voltage signal back from the rocker arm oil pressure switch.
The rocker arm oil pressure switch is a part of VVT variable valve timing. Some vehicles use a Variable Timing and Lift (VTEC) system.
There are differences between vehicles of different years and makes, so be sure to get a diagram for your specific car or truck.
Possible Causes of a P2646 Code:
Engine Oil Low or Dirty
Rocker Arm Oil Pressure Sensor/Switch
Variable Timing Oil Control Valve
Wiring Issue
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