Description

The following information is a brief summary of the procedure in this bulletin.

If the "Check engine" light is illuminated on the instrument panel and DTC 31 is retrieved by the Scan Tool, check the knock sensor and its wiring harness for continuity. If the knock sensor wiring harness checks out "OK", inspect the vendor number on the ECM. If the ECM is of the new style, test drive the vehicle to ensure that DTC 31 is not present.

If the vendor number on the ECM is of the old style and/or DTC 31 is still present after the knock sensor and harness are determined to be "OK", install a knock sensor modulator kit. Test drive the vehicle and recheck for DTC 31. If DTC 31 is not found, return the vehicle to the customer. If DTC 31 is still present, replace the knock sensor. After replacing the knock sensor, test the vehicle and return it to the customer.

To check the knock sensor wiring harness, inspect the ECM vendor number, and install the knock sensor modulator kit, refer to the following procedures:

CAUTION:
Observe standard shop procedures and safety practices while performing the procedures.

NOTE:
When needed, refer to the 1992-96 Diamante Service Manual for information not detailed in this bulletin.