Wide band O2 sensor ?

[Travis Moore]

Innovate Motorsports............NGK vs BOSCH sensor?

The differences between the sensors are:

1. Bosch has high heat sensitivity. It needs to be actively temperature controlled while the NTK has typically a passive temp. control by holding its heater voltage constant (very simple to do).

2. Bosch is sensitive to housing temp. NTK is not

3. Bosch has about 5-10 times faster response speed than NTK due to its planar design (measured delay time between pump cell current change and sensor cell output: NTK ~50msec, Bosch < 5 msec).

4. Bosch has less than 1/2 the NTK's sensitivity to back pressure. This means the readings are richer than actual on the rich side, leaner than actual on the lean side when on the lean side when back pressure is present.

5. Bosch sensor heats up more than twice as fast than NTK. This means it's also more susceptible to heat shock from condensation water because the NTK's slower warmup allows the exhaust system to warm up before the sensor can be damaged. The Bosch's fast warmup is required for smog reasons (it's main application). On the other hand the NTK is a more open design that is more susceptible to damage when hit by debris or water when hot.

6. With respect to survivability with leaded fuel they are about equal.

For most tuning applications, specially where fast response is required (not steady state load) the Bosch is the better sensor to use. The slower response of the NTK causes 'smearing' of the values. This leads to prettier graphs. A case of pretty vs. true and real (as it's often with girls).

Regards,
Klaus

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NGK Pages 3 & 5

http://www.ngksparkplugs.com/pdf/AFX_Tuning_Manual_Rev04.pdf

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That is all fine and dandy for internet talk, but in the real world, the NTK sensor is superior. There are no reported cases of a NTK sensor failing due to leaded fuel, but if you run leaded on a Bosch, you are on borrowed time.

 

[HAMMER]

NGK (NTK) and BOSCH both say accuracy will be degraded with leaded fuel. The only way to know by how much is to test exposure vs quantity vs time while calibrating them at intervals against a known laboratory standard. I'm sure the guys in the white lab coats that engineered them have done this hence do not recommend leaded fuel and refer to it as a contaminant. I was one of those lab guys for USAF aircraft systems electronic test equipment so I have a some precision calibration background. There's a huge grey area here between new and complete failure. If you need a precise and accurate reading throughout the usable range of the sensor you should take the necessary precautions. Like following the sensor manufacturers recommendations and calibrate it as recommended. Otherwise your readings may not be as accurate as you think. In the link I posted earlier NGK (NTK) recommends you calibrate their sensor once every hour if used with leaded fuel. The most stringent of all the recommended calibration cycles. That right there is telling you something.

The reality is, and I'll quote the NGK (NTK) installation guide.

"The AFR sensor should be considered an expendable part, a cost of tuning, just like gasoline and your time."

Happy Tuning !!!

 

[Travis Moore]

I've ran over 600 gallons of leaded fuel through a NTK sensor with NO problems and NO changes in readings(tuned the car with it early on, always read the same).