P033B OBD II Trouble Code Knock Sensor 4 Circuit Range/Performance Bank 2

Detailed information on troubleshooting and repairing a P033B DTC code which has to do with a range performance problem on the bank 2 knock sensor 4 circuit. Also includes links to relevant forum topics on the code.

Symptoms of P033B OBD II Trouble Code

  • MIL (Malfunction Indicator Lamp) illumination
  • Audible knocking from the engine compartment
  • Pinging from engine under acceleration

Common Causes of P033B OBD II Trouble Code

  • Knock sensor circuit is shorted to voltage
  • Knock sensor has failed
  • Knock sensor connector is damaged
  • Knock sensor circuit is open or shorted to ground
  • Moisture in knock sensor connectors
  • Incorrect fuel octane
  • PCM has failed

Severity of P033B OBD II Trouble Code

If the PCM determines that the knock is out of the ordinary or that the noise level is abnormally high, P033B may set. If the PCM senses that the knock is severe and cannot be eliminated by retarding the spark timing, P033B may set. Keep in mind that knock sensors cannot distinguish between a knock from pre-detonation or one from engine problems.