Mass Airflow Sensors and 750s <E32> <M70> <long>

[RangeR BoB <samurai@xxxxxxxxxxxx>]

Howdy!

	I have been getting occasional glimpses of the EML monster now and
again.  Engine shuts down to 6 cylinders, runs poorly, EML light comes
on, etc.

	When I check the "check engine light" to give me the code ("what's the
code Murray!") I find it used to give me 2215, which is the 
"AFM" for the right left cylinder bank (it lives up on the right side of
the motor, being a cross-flow design).  So, not having a manual (yet)
for the car, I enquired of this worthy list about the AFM on the car.  I
was told that you could renew it by popping off the cover and cleaning
the resistor that is moved back and forth by the moving metal flap.

	I hadn't been visited by the monster in a while, so like a good
American, I put it off.  It happened again, as I was getting ready for a
trip to San Antonio.  EML strikes again!  I checked the code, and darn
if this time it was 1215, or the sensor for the other bank of cylinders.

	Up comes the hood, out comes the air filter cover and MAF.  Yes, I mean
MAF, as in hot-wire Mass Airflow Sensor, not the classic moving vane
AFM.  Oops.  No user servicable parts that I know of?

	So now I am in a quandry.  I haven't gotten a factory ($) 750 manual,
and I also haven't bought a 3/5 series manual because so much is
different between the V-12 cars and the 6es.  Like AFM vs MAF.

	Does anyone know how to test a MAF?  I suppose I could go to the
dealer, and for the cost of 2 brand new ones, he could stick me with
$68/hr labor to tell me they are bad.  Or I could blow $700 on a pair of
new ones.  What I'd really like to do is check and see what is wrong.

	The MAF is wired with a miltipin cannon plug, and I cleaned both of
those out with contact cleaner.  I changed the air filters (not new, but
not plugged or bad).  I tightened up all of the clamps on the air boots
from filter box to MAF to engine.  Nothing else appears perished or
bad.  I got in and cranked it up and got EML again.

	Suggestions?  Could something else cause this kind of error?

	Thanks for the time and space.
- --

RangeR 
  BoB
Hembrook

'89 BMW 750iL                   "Sputnik"         94k
'89 Suzuki Samurai 4x4          "Sammy"           95k
'88 Kawasaki ZX-10                                28k

------------------------------

End of bmw-digest V9 #217
*************************