Engine Controls

WARNING: This page is about a different car, the 2003 Audi allroad, 2003 Audi TT, 2003 Audi S6, 2003 Audi A6, and 2003 Audi A4. However, it is still accessible from the selected car via links, so may be relevant.

Vehicles equipped with powertrain control computers may require a computer relearn procedure after the vehicle battery is disconnected or powertrain control computer is replaced. Vehicle computers memorize and store vehicle operation patterns for optimum driveability and performance. When the vehicle battery is disconnected, this memory is lost, which may result in a driveability problem. Depending on the vehicle and how it is equipped, the following driveability problems may exist:

Rough or unstable idle.
Hesitation or stumble.
Rich or lean running.
Poor fuel mileage.
Harsh or poor transmission/transaxle shift quality.

Default data is used until NEW data from each key start is stored. As the computer restores its memory from each new key start, driveability is restored.

Driveability problems may occur during the computer relearn stage. To accelerate computer relearn process after battery disconnect, specified computer relearn procedures should be performed.