Originally Posted by bananaman
Maybe I'll tape an interview with Jason at Mischler's BMW. So that he can clarify what he meant by "bad O2 sensor." My O2 sensor wasn't non-functioning. My O2 sensor was mal-functioning, resulting in the engine running full-rich.
In neutral, under no load, I could redline. Under load, 1st gear, redline. 2nd gear, redline. 3rd-5th gear, 65mph maximum speed.
Maybe I could re-install the bad O2 sensor... P
Bananaman, the detatails help us to understand your experience. However I am still having difficulty imagining how any
malfunction of the lambda can limit top speed, or what is meant by "engine running full rich" (from lambda sensor input). The motronic 2.2 is designed to ignore out of range signals from lambda by defaulting to a slightly
richer idle and steady state cruise. Clearly you value and trust the opinion of your shop. Is it possible that while the lambda was faulty this was only coincidental to your complaint of limited top speed? Did you try disconnecting the sensor before replacing it? The point of this is to assist others in understand how motronic 2.2 uses different sensor inputs and what to check first when encountering very poor performance such as you described. TPS and HES sensors are critical, lambda is not. Did you discuss this opinion with your shop? You can always disconnect the new lambda sensor and observe the effects.
Jim: Are you are saying that the life of the 1100 catalyst (U.S. models) will not be shortened if the lambda is disconnected for extended operation? I have not claimed to know the answer, instead, I posted that there was debate on that issue. Non-U.S. spec 1100 owners often mistake their pre-muffler/collector for a cat and ponder the absence of a lambda on their machines. Non-U.S. spec 1100 owners say they value the clarification because they find some of the motronic threads confusing.