Re: why the @#$@! do I need an O2 sensor-Car bette (archive)

Disconnected my O2 sensor this am as part of my ongoing search for cold driveabilty problem. It made absolutely no difference as far as warmup driving (O2 sensor not in loop afaik), but when warm car feels like I put another chip in it (already has a Jim C). Better, smoother pickup from low-midrange, car peppier in general. Idle now ROCK steady, instead of "normal" slight fluctuation from 700-800. So am I in grave danger of gumming up my cat, plugs etc? Doesn't feel/smell too rich to me... Or I am I just in danger of going below 10mpg in the city?
Seriously, If this is just a bandaid fix for another problem causing car to run too lean with O2 sensor, any ideas? Air leak, misadjusted AFM, bad DME??

Let me see,
An M6 has 300 HP with an O2 sensor and a Cat. I would assume if the 3.5 liter S38 motor can develop 300 HP get 20+ MPG on the highway and pass California emission test, your problem is any but the O2 sensor and Cat.
IMHO:
Diagnosing the Motronic problems is not simple. However, if your engine runs better without the O2 sensor you may have a clogged injector, vacuum leak, false air problem, bad O2 sensor and/or many other DME problems.

The technology behind the O2 sensor ended the problems of the mid 1970 vehicles and now cars like the E-28, M5 with 300 HP and E-39, M5 with 400 HP pass emissions test with flying colors and I assume you would agree they are not lacking in HP. Disconnecting an O2 sensor and removing the Cat will do nothing for HP and a lot to make you car part of the polution problem!!

Yes, running an engine with the O2 sensor disconnected will clog up or melt down the cat.

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