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 TestDFI System Troubleshooting Guide
NOTE
This is not an exhaustive list, giving every possible cause for each
problem listed. It is meant
simply as a rough guide to assist the troubleshooting for some of the more
common difficulties in
DFI system.
The ECU may be involved in the DFI electrical and ignition system
tro ...
Axle Inspection
Remove the front and rear axles (see Front/Rear Wheel
Removal).
Visually inspect the front and rear axle for damages.
If the axle is damaged or bent, replace it.
Place the axle in V blocks that are 100 mm (3.94 in.) [A]
apart, and set a dial gauge [B] on the axle at a point
halfway ...
Caliper Rubber Parts Replacement
Front Caliper Disassembly
Remove:
Front Caliper (see Front Caliper Removal in the Brakes
chapter)
Brake Pads (see Front Brake Pad Removal in the Brakes
chapter)
Remove:
Front Caliper Assembly Bolts [A]
Split the front caliper.
Remove:
Pad Spring
O-ring [A]
U ...