Engine Controls - Low Power/Won't Move After Stopping
37 Vehicle lacks power or will not move after stop
01 09 11
2003658/4
October 16, 2009.
Supersedes Technical DIAGNOSIS AND REPAIR Group 01 number 08-16 dated November 25, 2008 for reasons listed below.
Audi A4 Quattro Sedan (8K2) L4-2.0L Turbo (CAEB) Page 492
Affected Vehicles
Condition
Customer states:
^ Engine returns to idle speed of approximately 1,400 RPM although the accelerator is depressed.
^ Vehicle hesitates (lacks power on take-off).
Condition may be caused when the brake pedal and the accelerator pedal are depressed simultaneously.
Please review the driving habit of the client. Clients who consciously or unconsciously drive with their left foot resting on the brake pedal are prone
to experience this condition.
Technical Background
With the introduction of Electronic Power Control (EPC) (no accelerator cable) to fuel injection systems, an engine RPM control feature has been
incorporated into the engine electronic control system software.
Application of both brake and accelerator pedals at the same time (brake pedal with left foot and accelerator pedal with right foot) results in the
following:
^ Brake pedal function (normal at all times) overrides any throttle application.
^ Diagnostic Trouble Codes (DTCs) will not be stored.
If brake pedal is applied while accelerator pedal is depressed, after approximately two seconds, engine RPMs will return to idle speed of 1400
RPMs.
If accelerator is applied while brake pedal is depressed, vehicle accelerates slower than usual (reduced engine torque).
Production Solution
Not applicable.
Service
1. Test drive vehicle with customer to duplicate condition.
2. During test drive, observe customer's driving habits to determine if customer drives and/or brakes with his/her left foot.
3. After test drive with customer, connect a VAS diagnostic tool and check for any stored DTCs.
^ If DTCs are found, repair as necessary.
^ If no DTCs are found, explain the previously listed technical correlation between brake pedal and accelerator functionality to the customer.
-- Brake pedal overrides the accelerator pedal application at all times.
-- It is best not to drive with the left foot resting on the brake pedal.
Warranty
This TSB is informational only and not applicable to any Audi warranty.
Additional Information
All parts and service references provided in this TSB are subject to change and/or removal. Always check with your Parts Department and service
manuals for the latest information.
Audi A4 Quattro Sedan (8K2) L4-2.0L Turbo (CAEB) Page 493
