NOTICE
Never drop the air switching valve especially on a hard surface. Such a shock to the air switching valve can damaged it.

Air Suction Valve Inspection
Air Switching Valve InstallationAir Cleaner Housing Removal
Remove the fuel tank (see Fuel Tank Removal).
Disconnect the secondary fuel hose [A] from the delivery
pipe of the nozzle assy [B] (see Fuel Hose Replacement
in the Periodic Maintenance chapter).
Disconnect the secondary fuel injector connectors [C].
Free the lead from the grooves [D].
...
Cylinder Head Installation
NOTE
The camshaft cap is machined with the cylinder head,
so if a new cylinder head is installed, use the cap that
is supplied with the new head.
Install the dowel pins.
Replace the cylinder head gasket with a new one.
Replace the cylinder head bolt washers with new ones.
Apply molybden ...
Fuel Pump Relay Inspection
Refer to the Relay Circuit Inspection in the Electrical System
chapter.
If the fuel pump relay is normal, check the wiring to the
fuel pump relay (see Fuel Pump Relay Circuit).
Special Tool - Hand Tester: 57001-1394
If the wiring is good, check the ECU for its ground and
power supply (se ...