Ski-Doo 2005 MACH Z, Руководство по ремонту

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Section 04 ENGINE MANAGEMENT (SDI)
Subsection 01 (OVERVIEW)
FUEL INJECTION
The ECM receives the signals from different sen-
sors which indicate engine operating conditions at
milli-second intervals.
Signals from sensors are used by the ECM to de-
termine the injection parameters (fuel maps) re-
quired for optimum air-fuel ratio.
The CPS and TPS are the primary sensors used
to control the injection and ignition timing. Other
sensors are used for secondary input.
Flooded Engine Mode (Drowned Mode)
If the engine does not start and it is fuel-flooded,
this special mode can be activated to prevent fuel
injection and to cut ignition while cranking. Pro-
ceed as follows:
With tether cord cap on its post while engine
is stopped, press completely and HOLD throttle
lever.
Manual Start Models
Crank engine several times.
Electric Start Models
Press the START/RER button.
The engine should be cranked for 20 seconds. Re-
lease START/RER button.
All Models
In the engine drowned mode, engine cannot
start. It is required to release throttle lever and to
start/crank engine again to allow starting.
NOTE: If the engine does not start, it may be nec-
essary to replace the spark plugs.
IGNITION SYSTEM
The ECM is programmed with data (it contains ig-
nition mappings) for optimum ignition timing un-
der all operating conditions. Using engine operat-
ing conditions provided by the sensors, the ECM
controls the ignition timing for optimum engine op-
eration.
Engine RPM Limiter
The ECM will limit the maximum engine speed.
Knock Sensor
A knock sensor is mounted on top of the cylinder
head. It detects specific vibration that would be
typically generated by engine detonation. If deto-
nation occurs, the knock sensor detects it and the
ECMs retards the ignition advance and extend the
injection period temporarily (it goes in a specific
mode) until detonation stops.
ELECTRONICALLY CONTROLLED
RAVE (E-RAVE)
An electronically controlled RAVE (E-RAVE) sys-
tem with side exhaust port control is used. This
system offers more torque and less fuel consump-
tion in part load operation, compared to conven-
tional RAVE system.
A35C4MA
The opening of the valve is activated electronical-
ly by a rotary electronic actuator (REA). The ECM
monitors altitude, engine temperature, throttle po-
sition and RPM to operate the actuator for opti-
mum engine operation.
The RAVE valves are all either closed or fully
opened.
DIGITALLY ENCODED SECURITY
SYSTEM (DESS)
The following components are specially designed
for this system: ECM, tether cord cap and DESS
post.
This system allows the engine to reach pulley en-
gagement speed only if a programmed tether cord
cap is installed on DESS post.
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