Yamaha YZF-R25, Service Manual

Page: 331 / 456

THROTTLE BODIES
7-8
EAS30475
CHECKING THE INJECTORS (BEFORE
REMOVING)
1. Check:
• Injectors
Use the diagnostic code numbers “36–37”.
Refer to “SELF-DIAGNOSTIC FUNCTION
AND DIAGNOSTIC CODE TABLE” on page
9-5.
EAS30476
REMOVING THE INJECTORS
WARNING
EWA17330
• Check the injectors in a well-ventilated area
free of combustible materials. Make sure
that there is no smoking or use of electric
tools in the vicinity of the injectors.
• Be careful when disconnecting the fuel
hose. Any remaining pressure in the fuel
hose may cause the fuel to spray out. Place
a container or rag under the hose to catch
any fuel that spills. Always clean up any
spilt fuel immediately.
• Turn the main switch to “OFF” and discon-
nect the negative battery lead from the bat-
tery terminal before removing the injectors.
1. Remove:
• Fuel rail “1”
▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼▼▼
a. Remove the fuel rail bolts “2” as shown.
▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲▲▲
EAS30477
CHECKING THE INJECTORS
1. Check:
• Injectors
Obstruction
→
Replace and check the fuel
pump/fuel supply system.
Deposit
→
Replace.
Damage
→
Replace.
2. Check:
• Injector resistance
Refer to “CHECKING THE FUEL INJEC-
TORS” on page 8-94.
EAS30479
CHECKING THE THROTTLE BODIES
TIP
Before checking the throttle bodies, check the
following items:
• Valve clearance
• Spark plugs
• Air filter element
• Throttle body joint
• Fuel hose
• Air induction system
• Exhaust system
• Crankcase breather hose
WARNING
EWA17850
If the throttle bodies are subjected to strong
shocks or dropped during checking, replace
them.
1. Check:
• Throttle bodies
Cracks/damage
→
Replace the throttle bod-
ies.
EAS31367
CHECKING THE THROTTLE BODIES AND
ISC (IDLE SPEED CONTROL) VALVE
1. Remove the throttle bodies from the vehicle.
TIP
Before removing the throttle bodies, disconnect
the throttle cables and couplers.
Cleaning the throttle bodies
1. Clean:
• Throttle bodies
NOTICE
ECA20910
• Observe the following precautions; other-
wise, the throttle bodies may not operate
properly.
• Do not open the throttle valves quickly.
• Do not subject the throttle bodies to exces-
sive force.
• Wash the throttle bodies in a petroleum-
based solvent.
• Do not use any caustic carburetor cleaning
solution.
• Do not apply cleaning solvent directly to
any plastic parts, sensors, or seals.
• Do not directly push the throttle valves to
open them.
2
1