Download PRE - PRODUCTION ISSUE

ENGINE CONTROL SYSTEM
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AIR INTAKE COMPONENTS
Air, after entering through the silencer case, passes through the throttle bodies and flows into the collector
assembly (surge tank) where it is then distributed to the cylinder intake manifold.
Collector assembly (surge tank) pressure, monitored by the MAP sensor, is an indirect measure of the
intake air amount.
When the throttle is fully closed, the main supply of collector assembly (surge tank) air necessary to sustain
engine idle passes through the by-pass air passage.
To maintain engine idle speed at specification, the ECM controlled IAC valve supplies a regulated amount of
additional air through the IAC (idle air control) passage.
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Air flow
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6
1. PORT throttle body
2. STBD throttle body
3. IAC valve
4. By-pass air screw
5. Collector assembly
6. Throttle position sensor
7. MAP sensor
8. IAT sensor
9. Air intake silencer
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THROTTLE BODY
• Two throttle bodies are located on top of the collector assembly.
• The PORT throttle body assembly consists of the main bore,
throttle valve, by-pass air passage, by-pass air screw and
TPS (Throttle position sensor).
• The STBD throttle body assembly consists of the main bore
and throttle valve.
• The throttle body adjusts the intake air amount with the throttle valve which is connected to the throttle lever linkage.
• The TPS installed on the PORT throttle body informs of throttle valve opening angle.
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2
1. PORT throttle body
2. STBD throttle body
NOTE:
Do not try to adjust or remove any of the throttle body component parts (Throttle position sensor, throttle valve, throttle stop
screw, etc.).
These components have been factory adjusted to precise specifications.
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1. TPS
2. PORT throttle body