Display group 23 -Ignition- Knock control

WARNING: This page is about a different car, the 2002 Volkswagen Cabrio, 2001 Volkswagen Cabrio, and 2000 Volkswagen Cabrio. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Identifying Display Group 23 - Ignition (Knock Control)

Courtesy of VOLKSWAGEN OF AMERICA, INC.

For Evaluation 3 in Fig 1, see EVALUATING DISPLAY GROUPS 22/23, DISPLAY ZONES 3 AND 4 - RETARDATION OF IGNITION .
For Evaluation 4 in Fig 1, see EVALUATING DISPLAY GROUPS 22/23, DISPLAY ZONES 3 AND 4 - RETARDATION OF IGNITION .

Note on display zones 3 and 4:

The displayed value should be 0.0° CA at idling.

EVALUATING DISPLAY GROUPS 22/23, DISPLAY ZONES 3 AND 4 - RETARDATION OF IGNITION

Indicated on display	Possible cause	Corrective action
All cylinders greater than 15° CA	Knock sensor faulty	Check knock sensors. See IGNITION SYSTEM COMPONENTS, REMOVING AND INSTALLING .
	Connector corroded
	Knock sensor incorrectly tightened	Loosen knock sensor and tighten to 20 Nm
	Ancillary components on engine loose	Tighten ancillary components
	Poor fuel quality	Change type of fuel
One cylinder deviates greatly from the others	Connector corroded	Check knock sensors. See IGNITION SYSTEM COMPONENTS, REMOVING AND INSTALLING .
	Engine damaged	Check compression pressures: COMPRESSION PRESSURE, CHECKING
	Ancillary components on engine loose	Tighten ancillary components