Circuit Description

Knock sensors are located on either side of cylinder block underneath lower intake manifold assembly. Sensor generates voltage when engine block vibrates due to knocking. ECM retards timing based on this voltage signal. DTCs P0325 and P0330 are set when there is no knock sensor signal to ECM with engine speed of 2000-5600 RPM. DTC P0325 is for knock sensor No. 1 on right bank. DTC P0330 is for knock sensor No. 2 on left bank. Possible causes are:

• Open or short in knock sensor circuit.
• Knock sensor (loose).
• Faulty ECM.