Information: Adaptation Of The DME (DFI) Control Unit

Information 

If the DME (DFI) control unit is replaced, it must be programmed using the PIWIS Tester 9718  . This adapts the DME (DFI) control unit to the vehicle, country version and equipment.

Before the DME (DFI) control unit is removed and replaced, a read-out of the vehicle data should be obtained (if possible) using the PIWIS Tester 9718  .

The PIWIS Tester 9718  instructions take precedence and in the event of a discrepancy these are the instructions that must be followed. Deviations may occur with later software versions. The description is based on the 25.0 version.

Information 

When replacing one of the following components >> DME (DFI) control unit and/or high-pressure pump (also when replacing the engine) <<  from the fuel system, the adaptations in the DME (DFI) control unit must be adapted to the system again.

Rough engine running is possible until the adaptations are completed.

Noticeable decreases in engine performance may also occur.

Fig 1: Locating 911 DME Control Unit

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

The following sequence must be followed in the correct order for the adaptation of the fuel high-pressure control system: 

1. PIWIS Tester 9718  must be connected to the vehicle. Start the PIWIS Tester.
2. Select vehicle type and DME/DFI  control unit.
3. Select the Actual values  menu and press [>>].
   WARNING: Test drive with the Tester connected

   • Driver impeded/steers off course during test drive
   • Danger to other people on the roads

   → When the Tester is connected and switched on, route the diagnostic cable so that the driver is not impeded.

   → Only get one other person to read off the values on the Tester.

   → Only drive the vehicle to achieve the RPM and speed ranges specified in the document in accordance with road traffic regulations and if the road, weather and traffic conditions are conducive to such driving.

4. Select Actual values  .
5. Select the Fuel high-pressure control system  filter and press [>>].
6. Select the required items and press [>>]:
   1. 6.1. B010_Fuel high-pressure adaptation range 1 
   2. 6.2. B020_Fuel high-pressure adaptation range 2 
   3. 6.3. B030_Fuel high-pressure adaptation range 3 
   4. 6.4. B040_Fuel high-pressure adaptation range 4 
   5. 6.5. B050_Fuel high-pressure adaptation range 5 
   6. 6.6. Engine temperature 
7. Start the vehicle and let the engine warm up. During the test drive, at an engine temperature of at least 55 °C  , see Tester value for engine temperature  , gradually approach the engine speed range of more than 2000 RPM, then switch from operation under load to overrun and maintain this operating condition for at least 5 sec. >> The leakage adaptation  has now been completed. This value cannot  be read out under the actual values  .

   Information 

   If it is not possible to drive at the specified speeds, the adaptation ranges 1 to 5 can also be achieved by increasing the engine load relative to the specified speed. A defined fuel throughput must be achieved for the adaptation to be completed.

   The specified time stipulation of 15 sec. is cumulative, i.e. the time may also be broken down into 5 + 5 + 5 seconds, for example.

8. Fuel high-pressure adaptation range 1  must be reached: gradually approach the speed range of 60 - 85 km/h (40 - 55 mph) and maintain this for at least 15 sec. The Tester indicates when the value changes upwards or downwards by 1.00. >> This completes the adaptation of range 1  .

   Information 

   If it is not possible to drive at the specified speeds, the adaptation ranges 1 to 5 can also be achieved by increasing the engine load relative to the specified speed. A defined fuel throughput must be achieved for the adaptation to be completed.

   The specified time stipulation of 15 sec. is cumulative, i.e. the time may also be broken down into 5 + 5 + 5 seconds, for example.

9. Fuel high-pressure adaptation range 2  must be completed: gradually approach the speed range of 120 - 140 km/h (75 - 90 mph) and maintain this for at least 15 sec. The Tester indicates when the value changes upwards or downwards by 1.00. >> This completes the adaptation of range 2  .
10. Fuel high-pressure adaptation of range 3, 4, 5  These ranges do not  need to be achieved for the adaptation drive.
    1. 10.1. Range 3 requires constant driving for 15 sec. in the speed range of 210 - 220 km/h (130 - 140 mph). >> Not required  for the adaptation drive.
    2. 10.2. Range 4 requires multiple full-load acceleration, each time for approx. 10 sec. at an engine speed of more than 4000 RPM. >> Not required  for the adaptation drive.
    3. 10.3. Range 5 requires multiple full-throttle acceleration, each time for approx. 10 sec. at an engine speed of more than 5000 RPM. >> Not required  for the adaptation drive.
11. Once ranges 1 and 2 have been adapted, the values must be between 0.75 and 1.25. If the values are < 0.75 or > 1.25, a fault is entered in the DME (DFI) control unit. If the values are in the stipulated range, another test drive must be performed for a distance of approx. 15 km/10 miles (if feasible >> combination of motorway, cross-country and city driving). It is important that the drive includes different load and RPM ranges.
12. If range 1 and 2 are not within the stipulated range, the fault memory must be read out and the cause of the fault entries corrected.
13. Following the test drive, check the fault memory. If there are faults stored, the cause of the fault entries must be corrected.