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Engine Operating Conditions, Checking




NOTE: Checks whether engine control module recognizes the engine operating modes idling, overrun, part throttle, enrichment, full throttle.


Special tools equipment
- VAG1551 scan tool or VAG1552 mobile scan tool with VAG1551/3B cable

Test conditions
- Coolant temperature must be at least 80 °C, See display group 04, display zone 3.

Test sequence
- Connect VAG1551 scan tool (VAG1552). Start engine and select "Address word" 01 of engine control module. Engine must be running at idling speed. (Connecting scan tool and selecting engine control module). Refer to "VAG1551 Scan Tool Tools and Equipment

Indicated on display


Rapid data transfer HELP
Select function XX


- Press keys 0 and 8 for function "Read measured value block" and confirm entry with Q key.

Indicated on display


Read measured value block
Input display group number XXX


- Press keys 0, 0 and 5 for "Display group number 5" and confirm entry with Q key.

Indicated on display: (1 to 4 = Display zones)


Read measured value block 5 ->
1 2 3 4


- Check whether control module recognizes operating mode (display zone 4):
- Idling:
As long as the engine is running at idling speed idling must be displayed
Display: Idling
- Overrun mode:
- Increase engine speed to above 3000 RPM.
- Close throttle abruptly.
As long as the engine speed is above 1400 RPM overrun must be displayed
Display: Overrun


NOTE: Below 1400 RPM idling speed will be recognized.


- Part throttle:
- Rev up evenly.
As long as the engine is being revved up evenly, part throttle must be displayed
Display: Part throt.
- Enrichment:
- Floor accelerator pedal (onto throttle valve stop).
Acceleration enrichment must be displayed briefly
Display: Enrichment

Observe the valid safety precautions when carrying out a road test Technician Safety Information

- Press -> key.
- Press keys 0 and 6 for "End data transfer" function and confirm input with the Q key.

If the specifications are not attained:
- Check throttle valve control module. Testing and Inspection
- Check DTC Memory, if necessary, repair any malfunctions and then Erase DTC Memory,Checking and Erasing DTC Memory. Refer to Displaying and Reading Trouble Codes/With Manufacturer's Scan Tool/Check DTC Memory (Function 02)" Check DTC Memory (Function 02)

- Read readiness code. If DTC memory has been erased or engine control module was disconnected from permanent positive, readiness code must be generated again: Refer to "Monitors, Trips and/or Drive Cycle (Readiness Codes)/With Manufacturer's Scan Tool/Displaying and Creating Readiness Codes/Readiness Code, Reading" Monitors, Trips, Drive Cycles and Readiness Codes

Engine code AWP, Refer to "Monitors, Trips and/or Drive Cycle (Readiness Codes)/With Manufacturer's Scan Tool/Displaying and Creating Readiness Codes/ Readiness Code, Generating" Monitors, Trips, Drive Cycles and Readiness Codes