What should a air-fuel ratio sensor read?
An ordinary oxygen sensor is really more of a rich/lean indicator because its output voltage jumps up to 0.8 to 0.9 volts when the air/fuel mixture is rich, and drops to 0.3 volts or less when the air/fuel mixture is lean.
What are normal AFR readings?
-At idle or a steady cruise, it is normal for your gauge to display an AFR value of 14.0:1-15.5:1 or 0.95-1.05 in lambda. -A naturally aspirated motor under high load will target an AFR value of 12.5:1-13.3:1 or 0.85-0.91 in lambda.
What is the fuel ratio of an A / F sensor?
The A/F sensor provides a range of fuel ratios as rich as 12:1 to as lean as 19:1. A rich signal is a negative current with a voltage signal below 3.3 V. A lean signal is a positive current with a voltage above 3.3 volts.
When does the air / fuel sensor become sensitive?
When the air/fuel ratio is stoichiometric (between .15 and .8 volt), the oxygen sensor’s voltage becomes very sensitive. This is due to the sensor being balanced between rich and lean conditions.
What does 0 mA mean on Honda fuel ratio sensor?
Honda will typically display the sensor current directly, no voltage conversion shenanigans. 0 mA represents stoich, negative current indicates lean, and positive current indicates rich. Have a close look at those current values: Around .4 mA during power enrichment, and 1.5 mA during fuel cut decel.
What is the voltage of an O2 sensor?
An ordinary O2 sensor produces a voltage signal of 0.8 to 0.9 volts when the air/fuel mixture is rich, then drops to 0.3 volts or less when the air/fuel mixture goes lean. The transition is quick and abrupt, so the PCM has to keep track of the back and forth rich/lean transitions to estimate the average air/fuel mixture.
What is voltage of air fuel ratio sensor?
The Genisys scan tool shows the voltage at .64 volt. This indicates the current air/fuel ratio is approximately 14.4:1, or slightly rich. The enhanced factory scan tool reports the linear A/F ratio sensor as AF B1 S1, with a voltage ranging from 2.4 to 4.0 volts. In this case, the voltage on the factory scan tool would be 3.2 volts.
An ordinary O2 sensor produces a voltage signal of 0.8 to 0.9 volts when the air/fuel mixture is rich, then drops to 0.3 volts or less when the air/fuel mixture goes lean. The transition is quick and abrupt, so the PCM has to keep track of the back and forth rich/lean transitions to estimate the average air/fuel mixture.
How does a wide range air / fuel sensor work?
When two zirconium dioxide cells are used together, they can provide information to the microprocessor on a wide range of A/F ratios. The WRAF sensor can accurately detect an air/fuel mixture in the rich of approximately 11.5:1 and a mixture in the lean of approximately 24:1.
When the air/fuel ratio is stoichiometric (between .15 and .8 volt), the oxygen sensor’s voltage becomes very sensitive. This is due to the sensor being balanced between rich and lean conditions.