Compression Pressure, Checking

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Special tools and workshop equipment required

Spark Plug Removal Tool 3122B
Compression Tester Kit VAG1763

Procedure

Fig 1: Identifying Ignition Coil Puller T40039 Removing Ignition Coils

Courtesy of AUDI OF AMERICA, LLC

Engine oil temperature at least 30 °C.
Battery voltage at least 12.5 V.

-- Remove all ignition coils, refer to IGNITION COILS, REMOVING AND INSTALLING .

NOTE:

Ignore items -1 and 3-.

-- Disconnect the connector -2- to the fuel injectors on the rear of the left cylinder head.

Fig 2: Disconnecting Connector To Fuel Injectors

Courtesy of AUDI OF AMERICA, LLC

NOTE:

Ignore items -1 and 3-.

-- Disconnect the connector -2- to the fuel injectors on the rear of the right cylinder head.

Fig 3: Disconnecting Connector From Oxygen Sensor

Courtesy of AUDI OF AMERICA, LLC

-- Remove the spark plugs with Spark Plug Removal Tool 3122B.

-- Check the compression using the Compression Tester Kit VAG1763.

NOTE:

For information on using the tester, refer to the Operating Instructions.

-- Have a second mechanic press the accelerator pedal down all the way while operating the starter until the pressure increase is no longer displayed on the tester.

-- Repeat procedure on each cylinder.

Compression Pressure	Pressure
New	11.0 to 14.0 bar (160 to 203 psi)
Wear limit	10.0 bar (145 psi)
Maximum difference between cylinders	3.0 bar (43 psi)

Assembling

Assembly is performed in the reverse order of disassembly, noting the following:

-- Install the spark plugs.

-- Install the ignition coils, refer to IGNITION COILS, REMOVING AND INSTALLING .

-- The faults were stored in the engine control module DTC memories Generate Readiness Code in Guided Functions because the connectors were disconnected and the engine was started, refer to Vehicle Diagnostic Tester.