Compression Pressure, Checking: Procedure

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Engine oil temperature: minimum 30°C (86°F)
Battery voltage minimum 12.5 V.

-- Remove the fuse for the Fuel Pump Control Module -J538-, refer to appropriate System Wiring Diagram.

-- Remove the ignition coils, refer to IGNITION COILS WITH POWER OUTPUT STAGES, REMOVING AND INSTALLING .

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

-- Check the compression using the Compression Tester Kit VAG 1763.

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
-	Engine codes CEUA/CTGA	Engine codes CGTA/CTFA
New	10.0 to 15.0 bar (145.037 to 217.556 PSI)	9.0 to 14.0 bar (130.534 to 203.052 PSI)
Wear limit	9.0 bar (130.534 PSI)	8.0 bar (116.030 PSI)
Maximum difference between cylinders	3.0 bar (43.511 PSI)	3.0 bar (43.511 PSI)

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

-- Install the spark plugs, refer to SPARK PLUGS, REPLACING .

-- Install the ignition coils, refer to IGNITION COILS WITH POWER OUTPUT STAGES, REMOVING AND INSTALLING .

-- Install the fuse for the Fuel Pump Control Module -J538-, refer to appropriate System Wiring Diagram.

-- If there are any faults stored in the DTC memory that occurring during testing, erase them on the Vehicle Diagnostic Tester, Guided Functions , check DTC memory , then generate readiness code .