When the engine is running, the air intake valve is lifting up.
If the valve does not operate properly, check the air intake solenoid valve hoses for leak.
If there are no leaks, check the air intake solenoid valve.

Air Intake Solenoid Valve Unit TestElectrical Leads
A two-color lead is identified first by the primary color and
then the stripe color. Unless instructed otherwise, electrical
leads must be connected to those of the same color.
Instrument
Use a meter that has enough accuracy for an accurate
measurement. Read the manufacture’s instructions ...
Brake Disc Wear Inspection
Measure the thickness of each disc [A] at the point where
it has worn the most.
If the disc has worn past the service limit, replace it.
Measuring Area [B]
Brake Disc Thickness Standard:
Front 5.3 5.7 mm (0.21
0.22 in.)
Rear 4.8 5.2 mm (0.19
0.20 in.)
Service Limit:
Front 5. ...
Exhaust Butterfly Valve Actuator Resistance Inspection
Turn the ignition switch to OFF.
Disconnect the exhaust butterfly valve actuator lead connector
(2 pins connector) [A].
Set the hand tester to the × 1 Ω range and connect it to
the exhaust butterfly valve actuator connector.
Special Tool - Hand Tester: 57001-1394
Measure ...