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UNDER CONSTRUCTION - I
need help with this one.....volunteers?! What is it? - as the name implies a sensor that
detects O (Oxygen) levels! Part of the Emissions Control system of
European bikes only it effectively detects the presence of un-burnt
fuel in the exhaust. On doing so air is injected
in to the exhaust system via the PAIR valve in an attempt to reduce
'polluting' emissions. (I
like techy stuff -tell me more)
Emissions Control -
TLRMan 04/2004
Let's start with the easy one...the pair valve just allows extra air
into the exhaust system to help burn off any extra fuel that doesn't
burn in the combustion chamber...It opens mostly on decel
conditions.
The O2 sensor works hand in hand with the ECU. The ECU is programmed
from the factory, to make changes to the air/fuel mixture to keep
the engine operating under the parameters set by the factory. this
is to keep emissions down, and supposedly keep the engine operation
more efficient. We all know it's there for more of emission reasons
than anything else. The O2 sensor send a voltage back to the ECU,
which in turn "compares" what the engine is doing in real time,
versus what the map parameters are set for. If the O2 sensor sends a
lean or rich signal, the ECU will adjust fuel, timing etc, to what
it's supposed to be doing set by the original operating
parameters...This handshaking between the ECU and the O2 sensor is
called a "Closed Loop System"
Right now, only the Euro bike have this system.
If you are to install a PCIII, and make changes to the injector
durations, the O2 sensor will "see" this, and tell the ECU to
compensate. Bypassing the O2 sensor, will make the ECU "blind to the
fact of what the engine is really doing, and will cause a FI alarm.
I'm not sure about this particular application, but most bypass
systems send a voltage to the ECU, that "Fakes Out" the ECU in to
thinking everything is within operational parameters, and this will
allow the PCIII to do it's job, without Fighting the closed loop
system.
The bikes in the US don't have the O2 sensor YET,...and work off of
set parameters that "Should" keep the engine running within designed
parameters, using the TPS, MAP and atmospheric sensors. This we also
know can be tweeked to provide better performance, considering the
bike is set up to run within our emission standards over here.
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