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Page 72/83
UltraGauge
Blue
™
User Manual www.ultra-gauge.com
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Wide O2 Sensor
Output lambda &
AFR
Gauge name
Range
Units
Abbreviation
Wide O2 Bank1 Sensor 1
lambda
0 to 1.999
O2
wO2 B1S1
Wide O2 Bank1 Sensor 2
lambda
wO2 B1S2
Wide O2 Bank2 Sensor 1
lambda
wO2 B2S1
Wide O2 Bank2 Sensor 2
lambda
wO2 B2S2
Wide O2 Bank1 Sensor 1
lambda
.
wO2 B1S1.
Wide O2 Bank1 Sensor 1
lambda
.
wO2 B1S2.
Wide O2 Bank2 Sensor 1
lambda
.
wO2 B2S1.
Wide O2 Bank2 Sensor 2
lambda
.
wO2 B2S2.
The ECU monitors the Wide band O2 sensor and outputs Lambda. Lambda is the measure of the
actual Air to Fuel ratio as compared to the ideal or Stoichiometric Air to Fuel ratio. It is a ratio
and has no units.
λ
= Air
MASS
/Fuel
MASS
(Actual)
Air
MASS
/Fuel
MASS
(Stoichiometric)
λ
= 1 = ideal mixture
λ
> 1 = lean mixture
λ
< 1 = rich mixture
See the
AFR
discussion at the end of this document
There are two possible sets of Lambda parameters returned by the ECU. One is current based
and the other voltage based. While there is only one set of sensors and it would seem that a
given vehicle would support either voltage or current, it is possible for the ECU to support both.
Current based lambda have a “.” (“
λ.” in the units)
in the description and abbreviation,
Voltage based lambda have a “
λV” in the units
. The value from both should be identical.
Barometric
Pressure
Gauge name
Range
Units
Abbreviation
Barometric
0 to 75.3
inHg
Baro
0 to 255
kPa
Barometric pressure
