Local non mercedes mechanic thinks its an o2 sensor....but also that it might be the CAT converter
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2001 Mercedes-Benz E430 Question: Car hesitates when accelerating gently from low speeds. Ok once it gets going
Answer #1patrick mannion from Greg Solow's Engine Room, March 15, 2012, 22:57Master
If it's not an obvious ignition problem it would be best to look at live sensor data and Mode 6 diagnostic information using a professional grade scan tool. He could compare operating waveforms on both banks of the engine to see if they differ from each other using an oscilloscope.
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