Yamaha YZ450FA Automobile User Manual


 
7-20
FUEL INJECTION SYSTEM
Fault code No. 14
Symptom
Intake air pressure sensor system malfunction detected. (clogged hole or
disconnected sensor)
Fail-safe system Able to start
Able to drive
Diagnostic code No. D03
FI diagnostic tool dis-
play
Intake air pressure
Checking method Crank the engine. (If the display value changes, the performance is OK.)
Item Item/components and probable cause Check or maintenance job Checking method
1 Intake air pressure sensor hose is
clogged, damaged, disconnected,
kinked, pinched, or twisted.
Repair or replace. Start the engine and
let it idle for approxi-
mately 5 seconds with
the throttle fully
closed.
After completing the
above operation,
check whether a fault
code number is dis-
played.
Fault code number
is not displayed
Service is finished.
Fault code number
is displayed Re-
fer to item 2.
2 Defective intake air pressure sensor. Execute the diagnostic
mode (diagnostic code No.
D03).
When the engine is
stopped, displays the at-
mospheric pressure ac-
cording to the elevation
and weather.
0 m above sea level: Ap-
prox. 101 kPa
1000 m above sea level:
Approx. 90 kPa
2000 m above sea level:
Approx. 80 kPa
3000 m above sea level:
Approx. 70 kPa
Display value does not
change Replace the sen-
sor.