Engine Operating Modes, Checking

Engine Operating Modes, Checking

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

Special tools and equipment
- VAG 1551 Scan Tool or VAG 1552 with cable
- VAG 1551/3

Check conditions
- Throttle cable adjustment must be OK, checking:
- Coolant temperature must be at least 80 degree C, see display group 04, display zone 3.

Test sequence
- Connect VAG 1551 Scan Tool ((VAG 1552). Start engine and select "Address word" 01 of engine control module. When doing this engine must be running at idle speed.


Indicated on display

Rapid data transfer HELP
Select function XX

- Press keys 0 and 8 for function "Read Measuring Value Block" and confirm entry with Q key.

Indicated on display

Read Measuring 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 Measuring Value Block 5 ->
1 2 3 4

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

As long as engine speed is above 1400 RPM overrun must be displayed, display:
- Overrun

NOTE: Below 1400 RPM idle speed will be recognized.

- Part throttle:
- Rev up evenly.
As long as engine is being revved up evenly, part throttle must be displayed in display:
- Part throttle

- Full throttle:
- Floor accelerator pedal (onto throttle valve stop).

Full throttle must be displayed briefly, display:
Full throttle

NOTE: A test drive may have to be performed to show "Full throttle" in display.

Observe the valid safety precautions when carrying out a road test.
- Press -> key.
- Press keys 0 and 6 for "End data transfer" function and confirm input with Q key.

If the specifications are not attained:
- Check DTC Memory, if necessary, repair any malfunctions and then Erase DTC Memory, checking and erasing DTC memory. DTC Memory Checking and Erasing
- Check accelerator mechanism for ease of operation.
- Check throttle position sensor, Checking throttle valve control module. Throttle Valve Control Module, Checking