Life of wide-band O2 sensor with leaded fuel

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Does anyone have knowledge as to the expected useful life of a Bosch wide-band O2 sensor used on a race engine running leaded fuel? I've heard everything from "a few minutes" to "several seasons of racing" and am thus totally confused.

Assuming that there really is a huge range of life, I'm wondering what variables are in play. Ones that come to mind might be:

Compression ratio
Lead content of fuel
Other chemicals in fuel
Sensor location
Exhaust Gas Temperature
Mixture
Sensor type (wide/narrow band, heated/unheated)

An allied question - once it is poisoned with lead and starting to go, does it give false readings? And, can they really be resurrected using a torch?

Thanks in advance!

Al Seim

 

[magnograil]

If you do a web search on O2 sensors you should be able to find out what materials are used and whether they are effected by lead. Catalysts are effected because of the platinum coating.
O2 sensors have to be at a minimum temperature to work (600F?) so there obviously is a maximum distance from the exhaust port that will work. The heated sensors are to bring them up to temperature faster and keep them there at idle when the exhaust cools too much.
If they are coated with carbon, they can be cleaned with a torch, burning off the carbon deposits. An acetyline torch can be used (rich/lean mixture) to check the output.
Have you tried the Bosch web site?

 

[newgsr]

The average life expectancy of a wide band O2 sensor when in operation with leaded gas is 50 hours.

 

[Fader]

In practical application use the Bosch LSU has a very limited life on leaded fuel, along with being 'delicate'. The sensor to use for racing apps on leaded fuel is the NTK L1H1/L2H2.

 

[franzh]

Sorry to say I lost three in one afternoon when someone placed by accident the wrong fuel tank at the lab. Life was measured by minutes.
I would state that there is no definitive measured reduction of life based on leaded fuel, just to say that the sensor will irrepairably degrade with the first exposure.
Magnograil is correct with his comments.
Franz

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[bobqzzi04]

As Fader said, the sensor to run is the NTK UEGO sensor, but the cheaper versions of these are still prone to failure with leaded fuel. The lab grade versions are better in this respect. If you can avoid starting the engine cold on leaded fuel, you can greatly extend the life of the sensor. My dyno operator is meticulous about this and the sensor he bought 11 years ago still works fine after thousands of runs on leaded fuel. (His previous one failed after 5 years when he dropped it on the floor).
ECM and Horiba are the only authorized distributors for the good sensors.