Yamaha YZ450FA Automobile User Manual


 
3-40
TROUBLESHOOTING
INSPECTION STEPS
If the aforementioned problems have occurred, perform the following inspection steps in the order
given.
Check that the fuel tank is filled with
fresh gasoline.
No good
Fill the fuel tank.
OK
Check that the fuel tank breather hose is
not clogged. (Refer to "INCLUDED
PARTS" section in the CHAPTER 1.)
No good
Repair or replace.
OK
Adjusting the engine idling speed(Refer
to "ADJUSTING THE ENGINE IDLLING
SPEED" section in the CHAPTER 3.)
No good
Adjust.
OK
Check that the fuel hose is connected
properly and is not kinked or pinched.
No good
Repair.
OK
Check the spark plug for dirt, the spark
plug gap, and the spark plug cap. (Refer
to "CHECKING THE SPARK PLUG"
section in the CHAPTER 3.)
No good
Clean or adjust.
OK
Check that the air filter element is in-
stalled correctly and is not clogged. (Re-
fer to "CLEANING THE AIR FILTER"
section in the CHAPTER 3.)
No good
Clean or repair.
OK
Checking the sensors, injector and igni-
tion coil connection.
No good
Repair or replace.
OK
Installed condition of ECU (Refer to
"CHECKING THE ECU" section in the
CHAPTER 7.)
No good
Repair.
OK
Check the assembled condition of the
throttle body, and check the throttle
valve and its surrounding parts for dirt.
No good
Repair or clean.
OK
Consult a Yamaha dealer.