2-20 PERIODIC MAINTENANCE
Periodic Maintenance Procedures
Connect the following parts temporarily.
Fuel Pump Lead Connector
Extension Tube [A]
Special Tool - Extension Tube: 57001-1578
Install the air intake chamber (see Air Intake Chamber
Installation in the Fuel System (DFI) chapter).
Plug the air switching valve hose end [A].
Start the engine and warm it up thoroughly.
Check the idle speed, using a highly accurate tachometer
Standard: 1 100 ±100 r/min (rpm)
Do not measure the idle speed by the tachometer of
the meter unit.
While idling the engine, inspect the throttle body vacuum,
using the vacuum gauge [B].
Throttle Body Vacuum
Standard: 33.3 ±2.7 kPa (250 ±20 mmHg) @75°C
(167°F) or more (at idle speed)
If any vacuum is not within specifications, check the throt-
tle body assy holder (see Throttle Body Assy Holder Re-
moval in the Engine Top End chapter).
If there is any damage, replace the throttle body assy
Remove the air intake chamber (see Air Intake Chamber
Removal in the Fuel System (DFI) chapter).
Remove the vacuum gauge hoses and install the rubber
caps on the original position.
Install the removed parts (see appropriate chapters).