Volkswagen Workshop Service and Repair Manuals

• ◆ Idling speed, ignition timing and CO content not adjustable.
• ◆ The idling speed is regulated by the throttle valve control part.
• ◆ The position of the distributor has no influence on ignition timing.
• ◆ The CO content is held to specification by the Lambda control. Faults in Lambda control will be detected by the self-diagnosis and stored in fault memory.

Special tools, testers and auxiliary items

• ◆ Fault reader V.A.G 1551 with cable V.A.G 1551/3

Test conditions

• ● No faults stored in fault memory
  , interrogating fault memory
• ● Engine oil temperature min. 80 °C
• ● Electrical consumers switched off (radiator fan must not run during the check)
• ● Air conditioner switched off
• ● Exhaust system must be free of leaks

Test sequence

• ‒ Connect fault reader V.A.G 1551 (V.A.G 1552) and select engine electronics control unit with the "Address word" 01. When doing this the engine must be running at idling speed.
  (Connecting fault reader and selecting engine electronics control unit => Page 01-6 .)

• ‒ Press keys 0 and 4 for "Perform basic setting" function and confirm entry with Q key.

• ‒ Press keys 0, 0 and 1 for "Display group number 1" and confirm entry with Q key.

Note:

In the "System in basic setting" function the activated charcoal filter solenoid valve 1 (N80) is closed.

Do not continue with check until engine temperature exceeds 80 °C (display field 2).

• ‒ Briefly increase engine speed (rev- up) and then allow engine to run at idling speed for 2 minutes.
• ‒ Check specifications (display zones 1...4):

     1)     Up-to-date specifications:

=> Exhaust emissions test binder

• ‒ Press ⇒key.
• ‒ Press keys 0 and 6 for the "End data transfer" function and confirm input with the Q key.
• ‒ Carry out road test and repeat the check.
• ‒ Read-out the readiness code=> Page 01-35 .