Polaris 340 LX 2007, Руководство по обслуживанию

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BATTERY & ELECTRICAL SYSTEMS
DETONATION CONTROL (DET)
Overview
Detonation control is achieved by using a knock sensor mounted
to the cylinder head and an ECU (CFI engines) or the CDI
(600HO engines).
The knock sensor “listens” for combustion knock by converting
internal engine noise in to an electrical signal. The ECU or CDI
uses the signal to determine the level of knock within the
combustion chambers after each combustion event.
When the ECU or CDI determines detonation has occurred, the
CHECK ENGINE / DET LED lamp will blink on and off at 0.5
second intervals.
On CFI models, the ECU will retard timing and provide
additional fuel to eliminate the detonation. On carbureted
engines, the CDI will retard timing until the detonation stops. If
the detonation continues past a pre-determined level, the ECU
or CDI will initiate an engine mis-fire mode.
To prevent detonation, follow these steps:
• Always use premium fuel (91, 92, or 93 octane)
• On carbureted engines, follow the carburetor jetting
guidelines
• Do not modify the engine or exhaust system with non-
approved Polaris modifications
• Verify there is no water or foreign material in the fuel
• Verify there is no internal engine damage
• Verify the cooling system is working properly
NOTE: Install the knock sensor fastener clean and
dry without applying thread locker or oils.
VARIABLE EXHAUST SYSTEM (VES)
Overview
The Polaris VES system uses exhaust valves (1 per cylinder) to
control the exhaust port height. The valves are actuated by
controlling cylinder pressure with a solenoid, bellows, and a
series of hoses.
At idle speed and up to a pre-determined level, the solenoid is
powered by the ECU or CDI. This action opens the solenoid’s
internal valve and allows the cylinder pressure to vent into the
atmosphere. During this time the valves are down.
In order to raise the valves, the ECU or CDI will cut power to
the solenoid which will close the vent path to atmosphere. The
cylinder pressure will then act upon each valve bellows which
will raise each valve.
On CFI engines the timing at which the solenoid is turned off is
determined by engine RPM, TPS position, and pipe
temperature. On carbureted engines, the CDI will turn the
solenoid off at 6700 RPM when the throttle flipper is at least
3/4 throttle or at 7200 RPM when the throttle flipper is at least
1/2 throttle.
NOTE: Solenoid Powered = Vent Path Open
Solenoid De-Powered = Vent Path Closed