Suzuki Boulevard M50, Service Manual

Page: 258 / 454

FUEL SYSTEM AND THROTTLE BODY 6-23
• Turn the ignition switch OFF.
• Disconnect the STVA coupler.
• Turn the ignition switch ON.
• Open the secondary throttle valve fully by moving the fast idle
link with your finger.
• With the secondary throttle valve held at this position, mea-
sure the output voltage of the TP sensor as shown.
• Calculate the voltage difference between TP sensor output
voltage at idle and TP sensor output voltage with the STV full
opened.
Example: TP sensor output voltage with the STV fully open
Minus TP sensor output voltage at idle is 0.08 V

TP sensor output voltage variation: 0.064 – 0.096 V
• If the voltage variation is out of specification, loosen the
lock-nut
2
and turn in or out the fast idle adjust screw
3
to
adjust the voltage to specification.

• Cool down the engine to ambient air temperature and start the
engine to check the fast idle rpm comes within the specified
rpm.

Standard
Fast idle rpm: 1 500 – 2 100
rpm/Cold engine
Idle rpm : 1 100 ± 100 rpm/Warmed engine
• If it is not at the specified rpm, the cause may possibly be
short-circuit in water temperature sensor or wiring harness or
STVA.
The fast idle screw is factory-adjusted at the time of
delivery and therefore avoid removing or turning it
unless otherwise necessary.
STV fully open
Idle 1.20 V
- 1.12 V
0.08 V
SA
MP
LE