Airflow Inspection
1. Remove the vacuum hose..
2. Blow air into the vacuum hose using your mouth from the vacuum pump side and verify that the air flows to the intake manifold side, then blow air from the intake manifold side and verify that the air does not flow to the vacuum pump side.

If there is any malfunction in the check valve, replace it with the vacuum hose as a single unit..
Air Bypass Valve Inspection [Mzr 2.3 Disi Turbo]
Compression Inspection [Mzr 2.0, Mzr 2.5]If a warning light turns on or a warning buzzer sounds
If any warning indicator illuminates or a buzzer is activated in
your Subaru Solterra, remain calm and take appropriate action. A warning light that
briefly turns on and then goes off does not always indicate a malfunction. However,
if the issue repeats or persists, it is recommended to have t ...
Spark Plug Inspection [Skyactiv G 2.0]
Specification
Spark plug type
PE01-18110, PE02-18110, PE5R-18110, PE5S-18110
Plug Gap Inspection
CAUTION:
To avoid possible damage to the tip, do not adjust the plug gap.
To prevent damaging the tip, use a wire type plug gap gauge when inspecting
the plug gap.
...
Relay Block Inspection [With Advanced Keyless Entry And Push Button Start System]
1. Disconnect the negative battery cable..
2. Remove the following parts:
a. Driver-side front scuff plate.
b. Driver-side front side trim.
c. Hood release lever.
d. Upper panel.
e. Shift knob (MTX)(See MANUAL TRANSAXLE SHIFT MECHANISM REMOVAL/INSTALLATION
[G66M-R].)(See MANUAL TRANSAX ...