Audi Workshop Service and Repair Manuals

Notes:

• ◆ The idling speed cannot be adjusted.
• ◆ The idling speed is tested during the basic setting of the engine.

Test conditions

• ● No leaks in exhaust system
• ● Coolant temperature at least 80 °C
• ● Electrical consumers switched off (radiator fan must not run during the check)
• ● Air conditioner switched off
• ● Pressure gauge not connected
• ● Selector lever in position P or N

Special tools, testers and auxiliary items

• ◆ Fault reader V.A.G 1551 (or vehicle system tester V.A.G 1552) with cable V.A.G 1551/3

• ‒ Connect fault reader V.A.G 1551
  .
• ‒ Switch on ignition.
• ‒ Interrogate fault memory. The fault memory must be clear. If necessary, rectify any faults and erase the fault memory. Switch off the engine, then start up again. Take vehicle for a test drive and interrogate the fault memory again to make sure it is clear.
• ‒ Run the engine at idling speed.
• ‒ Switch off air conditioner.
• ‒ Switch off rear window heating.
• ‒ Place selector lever in P or N position (automatic gearboxes).
• ‒ Start basic setting of engine using V.A.G 1551 and continue until "Basic setting 1" appears on the display
  .

• ‒ Read off idling speed from display zone 1.

Specifications:

• ◆ Four-wheel drive: 620 ... 740 rpm
• ◆ Front-wheel drive: 740 ... 860 rpm

Note:

The increase in idling speed on vehicles with front-wheel drive occurs when the engine control unit receives a positive signal at contact 10 (from terminal 15).

• ‒ Press ⇒key.
• ‒ Press keys 0 and 6 for the function "End output" and confirm entry with the Q key.
• ‒ If the value does not match the specification, interrogate the fault memory again.

If the idling speed is too high or too low and there are no faults recorded in the fault memory, carry out the following tests:

• ● Testing idling speed switch .
• ● Large quantity of unmetered air
  =>Basic setting of engine, Display Groups 001, 005, 006 and 009
• ● Test throttle valve control part .