CAUTION:
After warming up the engine, it will be extremely hot. Be careful not to burn yourself while taking measurements.
1. Make sure that the battery is fully charged.
2. Disconnect the ground cable from battery.
3. Remove the collector cover.
4. Remove the air cleaner case (rear) and air cleaner element. 
5. Disconnect all fuel injector connectors.
6. Remove the intake manifold protector from intake manifold.
7. Remove the glow plug of the cylinder that will be measured.
CAUTION:
• Be very careful not to short the glow plug harness
• Be very careful when handling glow plugs.
8. Set the ST1, ST2 and ST3.
NOTE:
Illustration indicates cylinder #3.
| ST1 18367AA000 | COMPRESSION GAUGE ADAPTER |
| ST2 18367AA010 | COMPRESSION GAUGE ADAPTER |
| ST3 18831AA020 | GAUGE COMPL |
9. Connect the ground cable to battery.
10. Crank the engine and read the maximum value when the needle of the compression gauge becomes stable.
11. Measure each cylinder twice, and average the readings of the 2 measured values.
Compression pressure:
Standard
2.4 MPa (24.5 kgf/cm2, 348 psi)
Limit
2.2 MPa (22.4 kgf/cm2, 319 psi)
NOTE:
• The standard value and limit value shown above are obtained when ST1, ST2 and ST3 are used.
• Check that all cylinders are within specifications.
12. After completing measurement, attach parts in the order of step 7) to step 1).
13. Execute the Clear Memory Mode using the Subaru Select Monitor.
NOTE:
When disconnecting the fuel injector connector, the malfunction indicator light illuminates and DTC is stored in ECM memory.