Ignition System: Testing and Inspection

Misfiring Recognition, Checking

Special tools and equipment
- Scan tool V.A.G 1551 or vehicle system tester V.A.G 1552 with cable V.A.G 1551/3B

Test conditions
- Engine is OK mechanically.
- No DTC must be stored in the DTC memory. Refer to "Displaying and Reading Trouble Codes/With Manufacturers Scan Tool/DTC Memory Checking and Erasing" Testing and Inspection

Test sequence
- Connect scan tool V.A.G 1551 (V.A.G 1552). Start engine and select "Address word" 01 of engine control module. Engine must be running at idle speed. (Connecting scan tool and selecting engine control module). Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks/VAG1551 Scan Tool" Testing and Inspection

Indicated on display


Rapid data transfer HELP
Select function XX


- Press buttons 0 and 8 for function "Read Measuring Value Block" and confirm entry with Q button.

Indicated on display


Read Measuring Value Block
Input display group number XXX


- Press buttons 0,1 and 4 for "Display group number 14" and confirm entry with Q button.

Indicated on display (1 to 4 = Display zones)


Read Measuring Value Block 14 ->
1 2 3 4


- Check total number of misfires in display zone 3:
Specification: 0 to 5
- Check misfire recognition status in display zone 4:
Specification: activated

If the specifications are obtained:
- Press -> button.
- Press buttons 0 and 6 for the "End output" function and confirm input with Q button.
- Switch off ignition.

If the specifications are not attained:
- Change to display group 15 as follows:
- Press button 3 (VAG 1551) or button (Uparrow) (V.A.G 1552).

Indicated on display: (1 to 4 = Display zones)


Read Measuring Value Block 15 ->
1 2 3 4


- Check ignition misfires in display fields 1 to 3.
Specified value: 0 to 3
- Check misfire recognition status in display zone 4:
Specification: activated
- Change to display group 16 as follows:
- Press button 3 (V.A.G 1551) or button (Uparrow) (V.A.G 1552).

Indicated on display: (1 and 4 Display zones)


Read Measuring Value Block 16 ->
1 4


- Check ignition misfires in display field 1.
Specified value: 0 to 3
- Check misfire recognition status in display zone 4:
Specification: activated
- Press -> button.

If the specifications are obtained:
- Press buttons 0 and 6 for "End output" function and confirm input with Q button.
- Switch ignition off.

If the specifications are not attained:
- Check spark plugs and ignition/HT cables
- Check ignition transformers Testing and Inspection
- Check injectors. Refer to "Injectors, Checking" Testing and Inspection