Compression Check: Testing and Inspection
Compression, checking
Test requirements
^ Engine oil temperature at least 30°C.
^ Battery fully charged.
- Unscrew bolts -arrows- and remove engine cover panels -A...C-.
- Remove air duct -arrows-.
- Remove coolant reservoir-arrows and move it clear to side.
Note: Leave coolant hoses connected.
- Unplug connector from coolant level monitor.
- Remove cover panel from cylinder head cover (cylinder bank 4-6).
- Release hose clamp -arrow-.
- Remove intake pipe -1-.
- Disconnect hose -2-.
- Detach water pipe -3-.
Note: Plug lower section of intake pipe.
- Pull off hose -1-.
WARNING: Fuel system is under pressure. Before opening the system, place a cloth around the connection. Then release pressure by carefully loosening the connection.
- Disconnect fuel supply line and fuel return line -1- and -2- , and move fuel lines clear.
- Pull hose off EVAP valve -3-.
- Unplug connector -1- from air mass meter.
- Unplug connectors -2- from ignition output stages, and move wiring clear.
- Remove air cleaner.
- Remove cover panel from right-hand cylinder head cover-arrows-.
- Disconnect hose -1-.
- Disconnect hose -2-.
- Detach upper section of pressure pipe -3
Note: Plug lower section of pressure pipe.
- Pull crankcase breathers off cylinder head covers.
- Pull plug connectors off ignition coils.
- Remove ignition coils.
- Remove spark plugs.
- Unplug connectors from all 6 injectors.
- Remove fuse No. 28 (for fuel pump).
- Disconnect 5-pin connector at power output stage of ignition coils.
- Use compression tester V.A.G 1381 or V.A.G 1763.
- Open throttle fully.
- Operate starter until pressure reading on tester no longer rises.
Compression pressure values
Installing
Install in reverse sequence; note the following points.
- Fit fuse No. 28 (for fuel pump).
- Erase Diagnostic Trouble Code (DTC) memory.
Note: DTC'S will have been stored in the memory because the connector to the Hall sender has been unplugged. Therefore check and erase the DTC memory after the test.
Tightening torques