Engine Controls - Rattle From Intake Manifold On Startup
24 08 842017369/3
December 17, 2008.
Supersedes Technical Service Bulletin Group 24 number 08-17 dated April 15, 2008 for reasons listed below.
Affected Vehicles
24 Rattling from intake manifold
Condition
Sporadic hard metallic rattling sound from intake manifold only after first cold start, audible for 1-2 seconds.
Technical Background
Early activation of the vacuum solenoid valves for the variable intake manifold by the Engine Control Module (J623) during cold engine starts may cause the internal intake flaps to vibrate and create a brief rattling sound from the intake manifold.
Production Solution
New software in Engine Control Module (J623) resolved the intake manifold rattling issue.
Tip: Please explain to the customers that this new software is the latest software level with improved driving characteristics, which includes the following changes:
- The exhaust flap (if equipped) is always open, and no diagnosis of the Exhaust Flap Valve N321 is possible. Up to 1,700 rpm the engine is a bit louder, as the exhaust flap is always open.
- Faster throttle overrun cutoff, with more direct accelerator pedal and reduced overrun after releasing the accelerator.
- To prevent the clutch from slipping when accelerating from a stop, the engine torque is slightly reduced when vehicle speed is below 20 mph and the engine speed is higher than 4600 rpm. There is no noticeable performance difference.
Service
SVM Update Instructions
1. If you encounter a vehicle with a tuned ECM or TCM, your dealership must do the following before performing any procedure that updates ECM or TCM programming:
NOTE: Any Update Programming procedure (flash) may overwrite any tuned ECM or TCM programming. A tuned ECM or TCM is described as any ECM or TCM altered so as to perform outside the normal parameters and specifications approved by Audi of America, Inc.
a. Notify the owner that their ECM or TCM was found to have been tuned.
b. Notify the owner that any damage caused by the tuning of the ECM or TCM (including any adverse emissions consequences) will not be covered by Audi of America, Inc. warranties.
c. Obtain the owner's written consent (see Control Module Tuning form shown) for any requested repair - under warranty or outside warranty - that requires flashing that will automatically overwrite the tuned program.
2. Check the software part number and software level in the Engine Control Module (J623).
3. Prior to beginning the SVM process, insert a USB memory stick into the VAS 5051 tester to capture the diagnostic log electronically.
4. Connect the VAS 5051A and VAS 5051B to a 110 V AC power supply. The VAS 5051A and VAS 5051B must be connected to 110 V AC power supply at all times during the procedure.
5. Update the Engine Control Module (J623) using SVM action code as listed in the table below if necessary.
NOTE: Only VAS 6017B adapter can be used for this update. Usage of VAS 6017 or 6017A may result in complete control module failure.
- If the vehicle has a tuned ECM or TCM, ensure the Control Module Tuning form has been filled out by the owner.
Tip: The SVM Process must be completed in its entirety so the database receives the update confirmation response. A warranty claim may not be reimbursed if there is no confirmation response to support the claim.
- After updating the programming of the ECM, it is not necessary to set the Readiness Code.
For further SVM update instructions and troubleshooting, please refer to the SVM Operating Manual; ElsaWeb TSB 2011732.
Warranty
When procedure applies to vehicles under warranty, use the table.
Required Parts and Tools
- Approved charger.
Additional Information
The following Technical Service Bulletin will be necessary to complete this procedure:
- 2011732; Software Version Management (SVM) Operating Manual
All part and service references provided in this TSB are subject to change and/or removal. Always check with your Parts Dept. and service manuals for the latest information.