Ignition Timing: Testing and Inspection

REQUIREMENTS
^ Engine Oil Temperature 80°C (176°) minimum.
^ All electrical consumers switched OFF. Coolant Fan (radiator fan) must not run during check.
^ Air conditioner switched OFF.
^ Exhaust system must be free of leaks.
^ VAG 1551 Scan Tool (ST) connected.
^ No malfunctions stored in Diagnostic Trouble Code (DTC) Memory.

PROCEDURE
- Start engine and let idle.
- Operate Scan Tool while observing display.
- Press button -1- for "Rapid data transfer" operating mode.
- Press buttons -0- and -1- to enter address word 01 for "Engine Electronics."
- Press -Q- button to confirm input.
- Press --> button.
- Press buttons -0- and -4- to select the "Basic Setting" function.
- Press -Q- button to confirm input.

^ Indicated on display

Start basic setting HELP
Input display group number XX

- Press buttons -0- and -1- to select display group number 1.
- Press -Q- button to confirm input.

^ Indicated on display (1 - 4 = display fields)

System in basic setting 2 -->
1 2 3 4

NOTE: In the "Basic Setting" function, the Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80) is closed.

CAUTION Do not continue until engine temperature exceeds 80°C (176°), read in display field 2.

- Briefly raise engine speed, then allow engine to run at idle for at least 2 minutes.
- Read engine speed and ignition timing data:

^ Display field 1 = Engine speed
Specification: 650-750 RPM

^ Display field 4 = Ignition timing
Specification: 6° BTDC (fluctuating)

- Press --> button.
- Press buttons -0- and -6- to select the "End Output" function.
- Press -Q- button to confirm input.
- If engine speed RPM specifications are not obtained:

- Switch ignition OFF.
- Check accelerator pedal mechanism for ease of operation.
- Check throttle closing damper and adjust if necessary.