BMW DME Idle speed adjustment

The symptoms that you may need to do idle speed adjustment:
- Engine snapping at full steering lock.
- Increase/ reduce the idling speed when pulling away.
The idling speed of most DME modules can be adjusted using the AutoHex Diagnostic Scanner
Due to its adaptation, the engine will run at idling speed under the following conditions:
- Warming-up phase
- Low battery voltage
- The engine runs at idling speed for longer than 450 seconds
- The air conditioner is switched on
The normal idling speed cannot be adjusted while the engine is running at increased idling speed! For this reason, the following conditions must always be satisfied when adjusting the idling speed:
1. No fault stored in the DME fault memory. If necessary, rectify any fault stored and clear the fault memory.
2. Engine at standard operating temperature (coolant temperature above +85 °C.).
3. All electrical consumers must be switched off (air conditioner, headlights, heated rear window, etc.).
4. Adaptations must be cleared (AutoHex Diagnostic Scanner: Service functions, 3. Clear adaptation).
- Allow the engine to idle (not longer than 7 minutes! If this period is exceeded, increased idling speed can be returned to normal idling speed by opening the throttle briefly).
- AUTOHEX Diagnostic Scanner program: DME/DDE Motor electronics, Service functions, “Idle-speed adjustment”.

All currently selected idling speeds are displayed. In the event that not all idling speed values are set with deviation “0 rpm”, it must first be checked why modifications have already been made and whether these are still required.
- Depending on idling speed states, the engine speed can be adjusted by selecting the options in the following ranges: Idling speed state: Adjustment range:
1) Idling speed (normal) -60/+100 rpm
2) Idling speed with air conditioner on -60/+100 rpm
3) Idling speed with low battery voltage -60/+100 rpm
4) Idling speed with air conditioner -60/+100 rpm on and drive stage
5) Idling speed with a drive -60/+100 rpm stage engaged

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