Ignition System: Testing and Inspection
Misfiring Recognition, Checking
Special tools, test equipment and auxiliary items
- Scan tool V.A.G 1551 or vehicle system tester V.A.G 1552 with cable V.A.G 1551/3B
Test sequence
- Connect scan tool V.A.G 1551 (V.A.G 1552). Start engine and select "Address word" 01 of engine control module. When doing this the 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/VAG 1551 Scan Tool", Testing and Inspection
Indicated on display
Rapid data transfer HELP
Select function XX
- Press keys 0 and 8 for the function "Read measured value block" and confirm entry with Q key.
Indicated on display
Read measured value block
Input display group number XXX
- Press keys 0,1 and 4 for "Display group number 14" and confirm entry with Q key.
Indicated on display (1-4 = Display zones)
Read measured value block 14 ->
1 2 3 4
- Increase engine speed until display field 4 indicates the status-misfire recognition activated.
- Check the total number of misfires in display zone 3.
Display Group 14:
If the specification is not obtained, See Evaluating display group 14
If the specifications are obtained:
- Press -> key.
- Press keys 0 and 6 for the "End output" function and confirm input with the Q key.
- Switch off ignition.
If the specifications are not attained:
- Change to display group 15 as follows:
- Press key 3 (V.A.G 1551) or key (Uparrow) (VAG 1552).
Indicated on display (1-4 = Display zones)
Read measuring value block 15 ->
1 2 3 4
- Increase engine speed until display field 4 indicates the status-misfire recognition activated.
- Check the misfiring in display zones 1-3.
Display Group 15:
If the specification is not obtained, see Evaluating display groups 15 and 16
If the specifications are obtained:
- Change to display group 16 as follows:
- Press key 3 (V.A.G 1551) or key (Uparrow) (V.A.G 1552).
Indicated on display (1 and 4 = Display zones)
Read measured value block 16 ->
1 4
- Increase engine speed until display field 4 indicates the status-misfire recognition activated.
- Check misfiring in display zone 1.
Display Group 16:
If the specification is not obtained, See Evaluating display groups 15 and 16
- Press -> key.
- Press keys 0 and 6 for the "End output" function and confirm input with the Q key.
- Switch off ignition.
Evaluating display group 14, display zone 3 - total number of catalyst damaging misfires
Evaluating display group 15 display zones 1 to 4/display group 16 display zones 1 and 4 - catalyst damaging misfires Cyl. 1 to Cyl. 4
