P0028 - INTAKE VALVE CONTROL SOLENOID CIRCUIT RANGE / OUTPUT (BANK 2)

In a VVT system (Variable Valve Timing) the camshafts are driven by hydraulic actuators that are fed by the operating oil system of the engine through solenoids. This is managed by the PCM (Powertrain Control Module).

If the PCM observes that the camshaft movement on bank number 2 is not within the vehicle specifications or that the camshaft has not operated when commanded, the DTC P0028 OBDII code is set.

• Check Engine light illumination.
• The engine lacks power.
• The engine may run rough or stall.
• During acceleration, the engine may hesitate.
• Sudden slow motion
• Increased fuel consumption

The reasons that lead to the P0028 OBD2 fault code setting are:

• An oil level below the required level.
• There could be elements clogging the oil system.
• The intake valve solenoid could be shorted or have an open circuit.
• The electrical connections between the PCM and the solenoid may be shorted.
• Engine oil level too low
• VVL diagnostic switch failure
• VVT actuator failure
• Software failure requiring an update

To troubleshoot the P0028 OBDII error code you must do the following:

• Check that the engine oil level is necessary for a good operation of the system. Also, ensure that it is in an undamaged state. Replace it if necessary.
• Inspect the intake valve control solenoid. Replace it if necessary.
• Check the camshaft actuator as it may have defects that cause leaks. Also, check that the timing chain is in good condition.
• If the oil pressure is within specifications, perform a thorough inspection of all related wiring and connectors. Repair all defects as necessary, but be sure to check the circuit for reference voltage, continuity and ground contact. However, make sure to disconnect all control modules before beginning continuity checks. Refer to the appropriate manual to determine the color coding, location and function of each wire in the connector, as well as the exact reference voltage values.
• If repairs were made to the wiring/connectors, delete the code, operate the vehicle and rescan to see if the code is still present.
• If the code persists, there may be an ongoing fault and it might have to be left to get worse before an appropriate diagnosis can be completed.