If they appear damaged or deteriorated, replace them.

Balancer Adjustment
Torque LimiterSpecial Tools and Sealant
Compression Gauge, 20 kgf/cm²:
57001-221
Valve Spring Compressor Assembly:
57001-241
Valve Spring Compressor Adapter,
25:
57001-1019
Valve Seat Cutter, 45° - 27.5:
57001-1114
Valve Seat Cutter, 45° - 32:
57001-1115
Valve Seat Cutter, 32° - 28:
57001-1119
Valve Seat Cutter ...
General Information
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Engin ...
Air Intake Solenoid Valve Unit Test
Remove the air intake solenoid valve (see Air Intake Solenoid
Valve Removal in the Fuel System (DFI) chapter).
Set the hand tester [A] to the × 1 Ω range and connect it
to the air intake solenoid valve terminals as shown in the
figure.
Special Tool - Hand Tester: 57001-1394
...