Audi Workshop Service and Repair Manuals

Checking compression

Special tools and workshop equipment required

t	Spark plug socket and extension -3122 B-

t	Puller -T40039-

t	Torque wrench -V.A.G 1331-

t	Compression tester -V.A.G 1763-

t	Adapter -V.A.G 1381/5A-

Test sequence   Note t  Engine oil temperature at least 30 °C t  Battery voltage at least 12.7 V

–  Lift off engine cover -arrows-.

–  Remove bolts -1-. –  Unplug electrical connectors -2- from ignition coils and move wiring clear.

–  Remove ignition coils with output stages -2- using puller -T40039-. –  Remove spark plugs with spark plug socket -3122 B-. –  Unplug 8-pin connector for injectors → Item. –  Check compression pressure with compression tester -V.A.G 1763- and adapter -V.A.G 1381/5A-.   Note Using the compression tester → Operating instructions. –  Operate starter until pressure reading on tester no longer rises. Compression pressure:

Engine code letters	New pressure in bar	Wear limit bar	Permissible difference between cylinders bar
AXW, BLX, BLR, BVY	11.5	8.0	3.0 (maximum)
BHD, BMB, BLY, BVZ	10.5	7.0	3.0 (maximum)

–  Install spark plugs and ignition coils. –  Read out fault memory of engine control unit → Guided Fault Finding function of vehicle diagnostic, testing and information system VAS 5051.   Note Faults will have been stored in the memory because connectors have been unplugged. Interrogate and, if necessary, erase fault memory after completing the check. Tightening torques

Component	Nm
Spark plugs in cylinder head	30