Audi Workshop Service and Repair Manuals

Checking compression Special tools and workshop equipment required

t  Spark plug socket and extension -3122 B-

t  Compression tester -V.A.G 1763-

Procedure l  Engine oil temperature at least 30 °C. l  Battery voltage at least 12.5 V –  Remove engine cover panel -arrows-.

–  Remove air intake hose between air mass meter -G70- and intake manifold -arrows-.

–  Remove caps (left and right) -arrows-.

–  Disconnect all six spark plug connectors -arrows-. –  Remove spark plugs with spark plug socket -3122 B-.

–  Unplug 5-pin connector -1- from output stage of ignition coils -2-. –  Unplug electrical connectors at all injectors. –  Test the compression pressure with the compression tester -V.A.G 1763-.   Note Using the compression tester → operating instructions. –  Have a 2nd mechanic press down the accelerator pedal completely and simultaneously operate the starter until the pressure no longer increases on the tester display.

Compression pressure	bar
When new	9.0 … 14.0
Wear limit	7.5
Difference between cylinders	3.0 (maximum)

–  Install spark plugs → Rep. Gr.28. –  Interrogate and erase fault memory for engine control unit after testing compression pressure, as faults will have been stored when connectors are unplugged → Vehicle diagnosis, testing and information system VAS 5051.