Engine Controls - Rough Idle/Hesitation After Cold Start
SI B 12 01 03Engine Electrical
January 2003
Service Engineering
SUBJECT
E46 M3, E36/7 M roadster/coupe: Engine Runs Rough on Cold Start
MODEL
E46 M3 coupe/convertible with S54B32 from 03/01 up to 09/02
B36/7 M roadster/coupe with S54B32 from 02/01 up to 06/02
SITUATION
Customer may complain of the following:
^ Engine runs rough during the first 20 seconds of operation following initial cold start.
^ Engine hesitates, or there is poor throttle response during first 20 seconds of operation following initial cold start.
CORRECTION
On a customer complaint basis only, reprogram DME engine control module using DIS/GT1 CD 32.0 or higher.
IMPORTANT:
The new DME operating software will also limit engine speed to 6000 rpm, when vehicle is stationary (no road speed). This additional change was introduced into series production since 09/02.
PROCEDURE
To reprogram DME control module:
1. Connect vehicle to the BMW approved battery charger.
2. Connect DISplus/GT1 loaded with CD 32.0 or higher.
3. Select: BMW Coding/Programming
4. Select: 5 Programming, then right arrow
5. Select: 3 DME Programming, then right arrow
6. Select: 2 Exchange control unit, then right arrow
7. Display appears First determine and then program basic control unit, then right arrow
8. Select 1 Determine basic control unit, then right arrow. Automatic determination is going to be performed.
9. DME, is the faulty control unit still installed in the car?, select YES
10. Start automatic determination?, select YES
11. Display appears: Compare chassis number displayed with number in the car. Chassis number... Do numbers correspond? Select YES
12. Part number basic control unit.../... are displayed, then scroll down
13. Display appears: Followed part numbers (basic control unit) can likewise be used. A new program version is also programmed for these part numbers. Duration depends on control unit between 4 - 16 minutes, then scroll down
14. At this point vehicle data is stored in the tester for the automatic identification. Disregard screen prompt which refers to obtaining and installing a new basic control unit, and scroll to the left
15. Select: 2 Program basic control module, then right arrow
16. Follow instruction: Chassis number, enter the last 7 characters of VIN. Is the number correct? Select YES
17. Disregard the next instruction: Install new basic control module, just go forward by pressing right arrow
18. Display will appear: There is new program version and new data version for this control unit. Depending on the control unit, programming may last between 4-16 minutes. First programming and then data are programmed. After programming, with diagnosis program, the fault memories have to be cleared. EWS alignment is automatically carried-out with reprogramming. The adaptation values must be cleared after programming, then right arrow
19. The next screen displays: The control module can be programmed X times, then right arrow
20. Follow the command: Please enter reading mileage ... Entry correct? Select: YES
21. Start automatic programming? Select: YES
22. When programming starts, the following message is displayed: M5543 Program programming active. Voltage terminal 30
23. After programming part is finished , the following message is displayed: MSS43 data programming active. Voltage terminal 30......
24. After successful programming, message is displayed: Programming completed.
25. Next, follow-up screen instructions for EWS alignment and for clearing of adaptation values.
WARRANTY INFORMATION
Covered under the terms of the BMW New Vehicle Limited Warranty.
Note:
The following explanations will spell out the correct use of the work times.
Main Work:
Use this labor operation number when the only repair performed is the listed warranty repair.
OR
+Associated Work:
Use this labor operation number when other repairs or services are performed along with the listed warranty repair.
Under no circumstances should both labor operation numbers be claimed.
Attempts to claim both times will result in an unnecessary delay in claim processing and payment.