|The use of O2 eliminators has become fairly
common on the 2007 Harley-Davidson engines with aftermarket tuning devices.
When using an O2 eliminators supplied by PowerCommander, TFI, etc., the engine idles at a very rich 12.0:1
AFR during warm-up and forces the engine to run in open loop ECM operation
all the time. In some cases this will reduce
the engine temperature, but also reduces gas mileage 5-8MPG on an FLH and
can result in excessive carbon buildup in the combustion chamber. There
are ways to force the ECM into closed loop "learning mode" which
will cause the ECM to add fuel across the entire RPM range. Never assume
that this "learned" enrichment is going to be more than 2-3% and
you should never count on this being a permanent way to richen the fuel
mixture. Sometime in the future, Nightrider will go into more detail on
how to force the ECM into the learning mode.
This Do-It-Yourself O2
eliminator will cost you under $10 to make. The O2 eliminator is
nothing more than a 1 mega ohm resistor replacing the NBO2 sensor. All you
need to do is remove the O2 sensor and connect the resistor between the
Blue and Gray wires that run to the OEM sensor.
Recommended Upgrades for 2007 HD Twin Cam engine