Operation CHARM: Car repair manuals for everyone.

P0327

Diagnostic Chart:




Wiring Diagram:






The knock sensor is a piezoelectric device that produces an output voltage based on mechanical engine vibration. The PCM will retard the electronic spark timing on the signal being received. The knock sensor produces an AC signal. The amplitude and signal frequency is dependent upon the knock level. Upon diagnosis of the sensor circuit, the PCM will learn a minimum engine noise level at idle and compare to a noise level at around 2,000 - 3,300 rpm. This change does not necessarily mean spark knock is detected but that the sensor is giving the PCM a voltage signal based on the level of noise it sees. When the PCM monitors the circuit, it will set a DTC if there is no change in output from the knock sensor between idle and 2,000 - 3000 rpm.

DTC PARAMETERS

A DTC P0327 will set if:

There is an open or fault in the knock sensor circuit when:

^ The PCM has learned minimum a noise level at idle for five seconds and does not detect a change in noise level between 2500-3500 rpm for five seconds.

^ Engine coolant temp is greater than 65°C (149°F).

^ Engine run time is greater than 10 seconds.

^ Vehicle is moving to reach 2500-3500 rpm.

DIAGNOSTIC AIDS

When attempting to diagnose an intermittent problem use the Scan tool to review malfunction history diagnostic information. The supplemental data can be used to duplicate a problem.

Intermittents or opens suspected to be at the connector can be detected by using diagnostic service probe. Voltage can be read on wire without disconnecting any connectors.

^ The resistance to ground through the knock sensor should be around 100,000 ohms at 21°C (70°F).

^ A loose sensor could set P0327.

Torque: 15 N.m (133 in.lbs)

NOTE: The knock sensor has a different internal resistor and cannot be substituted for previous model years.