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 TestEngine Stop Switch Operation Inspection
First Step
Set the gear position in the neutral position.
Turn the ignition switch to ON.
Turn the engine stop switch to stop position [A].
Push the starter button.
The engine does not start.
If the engine starts, inspect the engine stop switch (see
Switch Inspection in the Electri ...
KIBS Servicing Precautions
There are a number of important precautions that should
be followed servicing the KIBS.
This KIBS is designed to be used with a 12 V sealed battery
as its power source. Do not use any other battery
except for a 12 V sealed battery as a power source.
Do not reverse the battery cable connec ...
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
...