Knock Sensor - Test Procedure
Group: 28Number: 92-01
Date: September 30, 1992
Subject:
New knock sensor checking procedure
Model(s):
Passat Syncro (with Engine code PG),
Canada Only
This bulletin supersedes TB number 91-03 (Repair Group 28) of November 30, 1991.
The following checking procedure replaces the information found on page 28-80-1 of the Passat Syncro Repair Microfiche.
Knock Sensor, checking
Vehicles WITHOUT On-Board diagnostic capability CANNOT have the knock sensor functionally checked.
The complaint "high speed not attainable" can be caused by an intermittent or nonfunctioning knock sensor.
Possible causes:
^ disconnected wiring
^ corroded terminals (poor or no contact)
^ knock sensor shield damaged
^ mounting bolt incorrectly torqued; must be 20 Nm (15 ft lb)
^ abnormal noises caused by:
^ torn or loose brackets
^ loose wiring
^ loosened components
^ broken, loose or missing bolts
^ mechanical damage
If NO fault found
^ replace knock sensor