Messages

1

Engine management / Stalling and Loss of Power on 1994 318is

« on: July 16, 2012, 07:30:54 PM »

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!

2

Engine management / code 1215 MAFS

« on: June 18, 2012, 02:31:08 PM »

I have been having power hesitation problems on my 1994 318is.  i have cleaned the mass airflow sensor, the idle control valve, and have replaced the valve cover and spark plugs.  The car is running better now, however, there is a breif loss of power when the engine temp is 1/2 way between cold and operating temp and this causes the the 1215 mass air flow sensor fault code.  I replaced the O2 sensor last year.  When the engine is cold or at operating temp, it seems to be running normally, although I can't test drive it completely as I'm concerned it may lose power.

The Bentley service manual suggests testing the mass airflow sensor resistance across pins 1 and 5 (I also tried 2 and 5).  The resistance does not change when I move the vain/door through all its travel with the sensor disconnected.  However, the when I test the voltage difference with the sensor connected and the ignition on the voltage changes when I move the door.  This means to me that a signal is being generated when airflow is changing, although I could be wrong.

Any comments would be appreciated.  Thanks!