wideband oxygen sensor

[hondance]

Just wondering if anyone out there done a conversion from conventional oxygen sensor to wideband oxygen sensor. according to some article i just read, wideband oxygen sensor provide a precise indication of the exact air/fuel ratio, and over a much broader range of mixtures - all the way from 0.7 lambda (11:1 air/fuel ratio) to straight air! as we all know, air/fuel ratio is critical with high performance, turbocharged and supercharged engines to make power and to keep the engine from leaning out at high rpm and boost pressures. If the mixture leans out, it can send the engine into self-destructing detonation.

[AcesHigh]

Wideband function for a daily driving is typically not recommended for several reasons. One, a wideband sensor is much more expensive than the stock narrowband and therefore you wouldn't want it to get damaged/dirty through daily usage.

Two, the driver to utilize the new hardware; in this case, a wideband O2 sensor, is not there. You can hook one up and install it in place of the stock sensor, but you probably won't be able to get it to run in conjunction with the stock ECU. Maybe you can modify it to make it work, I don't know.

Third, during acceleration the ECU is thrown into open loop mode; that is, it doesn't check with the oxygen sensor to determine the right amount of fuel; it derives the numbers from preset maps in its program. So even if you had a wideband working in there, it wouldn't be used anyways.

Widebands are only used during dyno tuning sessions, and in this time fuel maps are created and set into the ECU's program through chipping. In theory you could get that wideband and set the ECU on closed loop forever; you'd never have to tune, no matter what you did. But in real life this is simply not the case.

Aces

[AcesHigh]

I highly doubt that any manufacturer would install a factory wideband on a car; these new OBD2 cars have more narrowband O2's than OBD1, but not an actual wideband.

Perhaps this is the cause for confusion. The OBD2 performs as you describe; the O2 sensor typically taking in the information from the exhaust and then relaying to the ECU which adjusts fuel. OBD1 computers forgo O2 data altogether, unless in light or mild driving. OBD2 ECUs can be scanned by a handheld dianostics computer.

As I said before, wideband function in normal driving conditions would be expensive and highly impractical.

[boytiti]

Originally Posted by AcesHigh

I highly doubt that any manufacturer would install a factory wideband on a car; these new OBD2 cars have more narrowband O2's than OBD1, but not an actual wideband.

Perhaps this is the cause for confusion. The OBD2 performs as you describe; the O2 sensor typically taking in the information from the exhaust and then relaying to the ECU which adjusts fuel. OBD1 computers forgo O2 data altogether, unless in light or mild driving. OBD2 ECUs can be scanned by a handheld dianostics computer.

As I said before, wideband function in normal driving conditions would be expensive and highly impractical.

Wideband Air/Fuel sensor (5-wire oxygen sensor) is use on most top of the line OBDII cars. Wideband A/F sensors has been around for about 5 years now and its being used to lower emission. I know on my dads car, 2003 toyota camry, its not even top of the line car and its got wideband A/F sensor.