Compression Check: Testing and Inspection
Compression, checking
Special tools and equipment
^ Spark plug wrench 3122 B
^ Compression tester V.A.G. 1763
Test conditions
^ Engine oil temperature at least 30°C
^ Battery voltage at least 12.7 V
Test sequence
- Switch ignition off.
- Pull fuel pump fuse out of plug-in socket "28".
- Remove rear engine cover (arrows).
- Remove front engine cover (arrows -1- and -2-).
- Remove bolts (arrows) and coolant expansion tank -2-.
- Disconnect wire to engine coolant level (ECL) warning switch -F66- and lay aside coolant expansion tank with coolant hoses -1- and -3connected.
- Remove power steering reservoir cover (arrow).
- Remove bolt (arrow) at dipstick guide tube.
Note: Leave guide tube inserted in upper part of oil pan.
- Remove air cleaner cover -2-.
- Remove air duct -1
Note: Pull out clips (arrows) using pry lever 80-200.
- Disconnect connector -3- at evaporative emission (EVAP) canister purge regulator valve -N80- item -2-.
- Detach solenoid valve from holder.
- Disconnect connector -4- at mass air flow sensor.
- Turn hose -1- to secondary air pump counter-clockwise and detach.
- Detach air hose -5- at mass air flow sensor.
- Screw out bolt (arrow).
- Take out air cleaner housing with mass air flow sensor.
- Remove bolts -5- and -6- at left cylinder head.
- Disconnect connectors -1 -to -4-.
- Pull out ignition coils (arrows).
Note: Special tool T10094 can be used for removal.
- Remove bolts -5- and -6- at right cylinder head.
- Unplug connectors -1 -to -4-.
- Pull out ignition coils (arrows).
Note: Special tool T10094 can be used for removal.
- Use spark plug wrench 3122B to remove spark plugs.
- Fully open throttle valve.
- Use compression tester VAG 1763 to check compression pressure.
Note: How to use tester
Refer to Operating instructions
- Operate starter until no further increase in pressure is indicated by tester.
Compression values:
Assemble in reverse order, note the following:
The following operation must be performed on completion of compression test.
- As a final step, check and erase engine control module fault memory, as disconnecting fuse causes faults to be stored.
Vehicle diagnostic, testing and information system VAS 5051 is to be used for this purpose.
Tightening torques