narrow band oxygen sensor

[rus084]

our code can works with only wide band oxygen sensor :
http://sourceforge.net/p/rusefi/code/HEAD/tree/trunk/firmware/controllers/sensors/ego.cpp
do we need just add this code ?
case narrowBand:
sensor->v1 = 0.1;
sensor->value1 = 15;
sensor->v2 = 0.9;
sensor->value2 = 14;
break;

[AndreyB]

Done

[rus084]

thanks

[Tomin]

If sensor->v1 and v2 are values for "switchpoint", it is not a good idea, I think.
It should be somewhere arround 0.5V.
0.9V is too high for rich condition and 0.1V is too small for lean condition.
Some older lambdas tends to shift whole voltage characteristic down (even under 0Volts in lean !),
so 0.5Volt is more trouble proof approach.

[rus084]

we use interpolation , at 0,5v it will 14.5afr virtual .

[Number-One]

You are using one wire o2 sensor?

[rus084]

no , im using 4wire sensor . (+12v heater , gnd heater , gnd sensor , output sensor)
if your sensor is narrow band , this code will work with your sensor

[kb1gtt]

Single wire O2 needs the engine running for aprox 20 min before the O2 readings are used for tuning and adjustments.

4 wire (with heater) needs heaters turned on and engine running for aprox 5 minutes before O2 readings are used for tuning and adjustments.

The O2 readings are bogus until the sensor is warm. Some sensors turn off the heater after they have warmed up, some keep the heater on all the time.

[rus084]

i keep heater all the time . because if i turn off it , sensor works only at big engine load .

[puff]

probably, depends upon location of the sensor...

[rus084]

yes , my is far from cylinder head .

[kb1gtt]

Yes a sensor that's closer to the engine will need the heater less. If you are too close to the engine, you'll get to hot and shorten the life of your sensor. The heater control has many variations. Some will PWM after a while to help keep warm, but not over fatigue the sensor.

[Number-One]

I will fit my sensor in the final of the exhaust. 2 stroke engines are diferent, i can't use sensor after cylinder head.

[Tomin]

Single wire O2 needs the engine running for aprox 20 min before ...
4 wire (with heater) needs heaters turned on and engine running for aprox 5 minutes ....

It is totally overstatemented. 20 minut ? No, it is much faster.
5 minutes is also too long.
If you would like, I can find some link on youtube with live data on I4 Duratec engine just after cold start.
There is a closed loop in ?one? minute cca.

I think it is not a good idea to try read some AFR from narrow band sensor. You can use it for detect UNDER or ABOVE 14.7/stoich position only,
nothing more. Any interpolation from NB sensor is bad path, I think.