What does it mean?
This is a generic diagnostic trouble code (DTC) for the powertrain, meaning it applies to all makes/models from 1996 and newer. Specific troubleshooting steps vary by vehicle.
This P0366 code essentially means that the Powertrain Control Module (PCM) has detected a problem with the “B” camshaft signal. This DTC relates to engine bank 1, which is the cylinder bank that contains cylinder #1.
The Camshaft Position Sensor (CPS) sends a specific signal to the PCM for Top Dead Center on the compression stroke as well as signals indicating the cam sensor position. This is accomplished via a reluctor wheel attached to the camshaft that passes by the cam sensor. Whenever the signal sent to the PCM does not match what it should be, this code is set. NOTE: This code can also be set by extended cranking periods.
Symptoms
The car will likely run with this code set, as it is often intermittent and also because the PCM can often run the vehicle in “limp-in/limp-home” mode even with a cam sensor signal problem. There may be no noticeable symptoms other than:
Poor fuel economy (if the engine runs)
No-start condition possible
Check Engine Light illuminated
Causes
A P0366 code can mean that one or more of the following has occurred:
Cam sensor wiring routed too close to spark plug wiring (causing interference)
Faulty wiring connection to the cam sensor
Faulty wiring connection to the PCM
Faulty “B” cam sensor on bank 1
Damaged reluctor wheel
Possible Solutions
NOTE: In some cases, this engine code is set on vehicles that do not actually have a camshaft position sensor. In these cases, it essentially means the engine is misfiring due to faulty spark plugs, spark plug wires, and often coils.
Often, replacing the sensor fixes this code, but not necessarily. Therefore, it is important to check the following:
Check that wiring is not routed too close to secondary ignition components (coil, spark plug wires, etc.)
Visually inspect the sensor wiring for any burn marks, discoloration indicating melting, or chafing
Visually inspect the cam sensor for any damage
Visually inspect the reluctor wheel through the cam sensor port (if possible) for any missing teeth or damage
If the reluctor is not visible from outside the engine, visual inspection can only be performed by removing the camshaft or intake manifold (depending on engine design)
If everything checks out, replace the sensor.
Related Camshaft Fault Codes: P0340, P0341, P0342, P0343, P0345, P0347, P0348, P0349, P0365, P0367, P0368, P0369, P0390, P0366, P0392, P0393, P0394.