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Old 03-13-2006, 07:34 AM
Lscman Lscman is offline
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Location: PA
Join Date: Aug 2003
Posts: 344
Mein Auto: 540i 6spd
Originally Posted by Schnell5
Well I think you need another professional opinion before you go and buy anything more. Find out what the CEL exactly said. Where did it come from? How many miles are on your vehicle and have the sensors ever been changed?

If you do need the sensors, Autozone, yes Autozone sells the exact same BOSCH sensors with direct plug in end for a fraction of the price. (same BOSCH part number). fyi.
Very good point. Do not try alternative or generic O2 sensors. They need to be specifically calibrated to maintain proper fuel mixture and no thrown codes. If Auto Zone sells exact replacements for cheaper, go for it. I concur that O2 sensors can throw these codes. The DME computer can not tell the difference between defective O2 sensors and defective Catalytic converters. It only extrapolates and guesses based upon fore and aft O2 sensor outputs. If the O2 sensor is bad, the DME trouble code diagnosis can be bad as well.

The dealers aren't much better at determining root cause components in this regard.
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