Series 50G/60G Troubleshooting – Section 4.4 Verification of Engine Knock

Section 4.4
Verification of Engine Knock

Verify the engine knock codes are actual (real) or externally induced (fake) as follows:‪

1. Turn the ignition off.
2. Unscrew the Knock Sensor from the block.
3. Hang the Knock Sensor in the engine compartment.
4. Cut a 16 or 18-gage insulated copper wire 30 mm (12 in.) long. Cut the rubber sheath off both ends to expose 5 mm (2 in.) of the copper leads.
5. Wrap one end of the wire around the threads of the Knock Sensor (secure with electrical tape) and bolt the other end of the wire to a clean ground on the block.
6. Road test the vehicle.
7. Turn on the ignition. Plug the Diagnostic Data Reader (DDR) or the Detroit Diesel Diagnostic Link (DDDL) into the Diagnostic Connector.

   Note: Use the Pro-Link kit to connect the DDR. Use PC card installed in the computer to connect the DDDL .

8. Read active and inactive codes by selecting the DIAGNOSTIC CODE MENU (ACTIVE CODES) on the DDR or DDDL.
9. If the vehicle registers no knock codes, then the original knock codes are real. Check the Air Intake Components, refer to "4.5 Air Intake Components" .
10. If the vehicle still has knock codes then the original knock codes are fake and are being caused by wiring or bad grounds. Check the starter and block ground connections, refer to "4.14 Fake Knock Codes" .