Checking The Intake Manifold Joints; Checking The Fuel Pressure; Adjusting The Throttle Position Sensor - Yamaha Star XVS950A 2009 Service Manual

EAS5S71038
CHECKING THE INTAKE MANIFOLD
JOINTS
1. Check:
• Intake manifold joints
Cracks/damage → Replace.
EAS5S71016

CHECKING THE FUEL PRESSURE

1. Check:
• Fuel pressure
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a. Remove the fuel tank bolt and holdup the
fuel tank.
b. Disconnect the fuel hose "1" from the fuel
pump.
EWA5S71010
WARNING
Cover fuel hose connections with a cloth
when disconnecting them. Residual pres-
sure in the fuel lines could cause fuel to
spurt out when removing the hoses.
c. Connect the fuel pressure adapter "3"
between the fuel hose "1" and fuel pump
"2".
d. Connect the pressure gauge "4" to the fuel
pressure adapter "3".
Pressure gauge
90890-03153
YU-03153
Fuel pressure adapter
90890-03176
YM-03176
e. Start the engine.
f. Measure the fuel pressure.
Fuel pressure
392.0 kPa (3.92 kgf/cm
psi)
Faulty → Replace the fuel pump and pres-
sure regulator.
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EAS27030
ADJUSTING THE THROTTLE POSITION
SENSOR
TIP
Before adjusting the throttle position sensor,
the engine idling speed should be properly
adjusted.
1. Check:
• Throttle position sensor
Refer to "CHECKING THE THROTTLE
POSITION SENSOR" on page 7-104.
2. Adjust:
• Throttle position sensor angle
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the throttle position sensor cou-
pler to the throttle position sensor.
b. Connect the digital circuit tester to the
throttle position sensor.
• Positive tester probe →
yellow "1"
• Negative tester probe →
black/blue "2"
Digital circuit tester
90890-03174
Model 88 Multimeter with
tachometer
YU-A1927
c. Turn the main switch to "ON".
6-11
THROTTLE BODIES
2
, 56.9