Stalling and Loss of Power on 1994 318is

[m42mb]

I replaced the mass airflow sensor to correct stalling and loss of power.  The car runs much better.  However it still stalls for a couple of minutes when the engine temp is between cold and operating temperature.  

To trouble shoot this I disconnected the Oxygen sensor.  This seemed to cure the problem although I have to test drive it again.  I replaced the Oxygen sensor one year ago (Bosch 13231 from Amazon.com).

Anyone experienced a O2 sensor failing after one year?

Also, the maintenance advisor at the local BMW dealer mentioned that there is a calibration procedure after installing a new mass airflow sensor.  I can't seem to find any information about such a procedure.

Any comments would be appreciated.  Thanks!

[DesktopDave]

You should try out a stomp test.  It'll let you know what the motor thinks is wrong, if anything.  Google it if you don't know what I'm talking about.

Unless you're in Europe, all AFMs have been pre-calibrated by Rob't Bosch at his factory, no need for them to be adapted to the car.  IIRC some Euro cars don't run a catalytic converter...and so still use the CO pot adjustment.  Earlier Bosch FI systems like CIS-E & Jetronic needed a bit of tweaking to run at their best.  AFMs would be adjusted along with the throttle and idle control to get the best power/emissions compromise.

As far as the o2 sensor fail, it might be some other system that's causing it.  The heater circuit might be flaky, perhaps the relay is bad.  Could be a dying temp sensor as well.  I've seen o2 sensors still functional after hundreds of thousands of miles, but it should be replaced every 60K miles or so.  A newer sensor can save you fuel as well as wear and tear on the motor.

IMHO BMW dealers are a bit rusty on older cars like ours, they mean well though.