Misfire Recognition, Checking

Misfiring Recognition

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required
- Scan tool VAG 1551 or vehicle system tester VAG 1552 with cable VAG 1551/3

Test sequence
- Connect scan tool VAG 1551 (VAG 1552). Start engine and select "Address word" 01 of engine control module. When doing this the engine must be running at idling speed.
(Connecting scan tool and selecting engine control module). Refer "VAG 1551 Scan Tool" [1][2][3][4][5]Connecting VAG 1551 Scan Tool

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


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

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:
- Check the spark plugs and ignition/HT cables, Removing and installing parts of the ignition system Service and Repair
- Check ignition coils with output stages Testing and Inspection
- Check injectors Refer "Injectors, Checking" Testing and Inspection