Display group 2 -Basic functions- Mass air flow sensor

Fig 1: Identifying Display Group 2 Basic Functions - Mass Air Flow Sensor

Courtesy of VOLKSWAGEN OF AMERICA, INC.

Identifying Display Group 2 Basic Functions - Mass Air Flow Sensor

EVALUATING DISPLAY GROUP 2, DISPLAY ZONE 3 - INJECTION PERIOD

Indicated on display	Possible cause	Corrective action
Less than 2.0 ms	Large amount of fuel from EVAP system	Check EVAP canister purge regulator valve. See OUTPUT DIAGNOSTIC TEST MODE (DTM) (SCAN TOOL FUNCTION 03)
Less than 2.0 ms	Incorrect injectors with greater throughput installed	Check injection rate. See FUEL INJECTORS, CHECKING .
Larger than 5.5 ms	Increased engine load due to electrical consumers, air conditioner, gear selected or power steering on full lock	Eliminate increased load (air conditioner, power steering etc.)

EVALUATING DISPLAY GROUP 2, DISPLAY ZONE 4 - AIR MASS DRAWN IN

Indicated on display	Possible cause	Corrective action
Less than 2.0 g/s	Large amount of unmetered air between intake manifold and mass air flow sensor	Correct unmetered air
More than 5.0 g/s	Gear selected (automatic transmission)	Place selector lever in P or N
More than 5.0 g/s	Engine loaded due to ancillaries	Eliminate load (air conditioner, power assisted steering etc.)

Note on display zone 4:

Displayed is the air mass measured by the mass air flow sensor.
In emergency running caused by a malfunction on the throttle valve control module the engine runs without idling stabilization at an increased idling speed (approx. 1000 to 1300 RPM) via the emergency running gap. In this case the air throughput is approx. 4.5 to 5.5 g/s.
The replacement value in g/s from throttle position sensor will be displayed if the engine control module detects a malfunction on the mass air flow sensor.