Facing the frustrating P0366 error code? This code, indicating a “Camshaft Position Sensor ‘B’ Circuit Range/Performance (Bank 1)” issue, can be a real headache for car owners. One driver experienced this firsthand and sought expert help after initial fixes failed to resolve the problem.
Initially, the owner replaced the Camshaft Position Sensor (CPS) on Bank 1, often the first step in addressing P0366. However, this action unfortunately worsened the issue. Suspecting a faulty replacement part, another new sensor was installed, but the problem persisted. The car continued to exhibit random power loss during acceleration, almost as if entering a limp mode intermittently.
Seeking professional expertise, the vehicle was taken to a specialized and reputable garage known for diagnosing complex automotive problems. A thorough examination was conducted, starting with a mechanical inspection of the camshaft components. Mechanics meticulously checked the valve train under the tappet cover, including the camshaft itself, timing components, CVVT oil control valve, phaser, and bearings. All these components were found to be in perfect working order, eliminating mechanical failure as the primary cause.
Next, the focus shifted back to the Camshaft Position Sensor and its related electrical system. The sensor’s signal was analyzed using a diagnostic computer to check for proper pulse generation. During idle and stationary revving, the sensor appeared to function correctly. Intriguingly, the issue only manifested when the car was in motion and under acceleration. Wiring integrity was meticulously investigated, and all sensor and vehicle wiring was confirmed to be well-insulated and without apparent faults. Furthermore, the alternator and battery were tested and ruled out as contributing factors, eliminating general electrical system malfunctions.
To pinpoint the issue, a live diagnostic session was conducted while driving the car. Monitoring the Cam Duty Phaser percentage revealed a critical anomaly. The phaser duty cycle would rise normally during acceleration, but then unexpectedly drop to 0%. This sudden drop coincided precisely with the instances of power loss, suggesting the engine was momentarily going into a protective safe mode. The erratic nature of these drops, occurring randomly across different RPM ranges, ruled out any consistent engine speed-related problem.
Click here to watch the video of the phaser issue on youtube
Despite extensive testing of mechanical and electrical components related to the Camshaft Position Sensor “B” circuit, the root cause of the P0366 code and intermittent power loss remains elusive. This case highlights the complexity of diagnosing such issues and the need for further expert insights to resolve this challenging automotive problem.
