Corrections to MAF/AFM information

[Jim Conforti <lndshrk@xxxxxxxxxxxx>]

mark kibort writes: (and Shark corrects in his typical Politically
                     Incorrect style)

> Thanks for your response. Make no mistake , a AFM is a mass flow device.
> very accurate as

  BZZZZT.. wrong.. thank you for playing.. (next contestant) *grin*

  THE AFM measures VOLUME flow rates.. which must be corrected for 
  Pressure and Temperature to become "mass equivalent"

  It does NOT measure mass.. not at ALL.. whomever is telling you
  this needs to go back to school.

  This difference is ALSO the reason you HAVE TO reWRITE DME code
  to do a *PROPER* AFM-to-MAF swap.. you now have to REMOVE all
  that compensating code for Altitude and Temp air density corrections

> at altitude where the air may be 3% less dense, for the
> same air speed  in to the engine, you would have less dense air thus
> deflecting the flapper valve less and creating less voltage for the ECU
> signaling less fuel.  

  Actually it DOESN'T do that.. it signals the EXACT SAME amount for
  the SAME VOLUME FLOW RATE.. which is why on many cars you have a 
  BAROMETRIC PRESSURE sensor.. or Adaptive Lambda to compensate for
  the Altitude Density of Air.

> One of the only limitations is its max point.   at which time, 
> the system goes uses only RPM to increase fuel injector duration.

  Another fallacy.. you must be reading the BOSCH book on L-Jetronic
  and tranferring it to Motronic.. but it don't work that way..
  
  AT EVERY POINT, the DME takes the AFM/HFM signal.. and with RPM
  and a constant (Injector Constant) forms a BASE INJECTOR DURATION
  known in Boschland as LOAD or Tl (Tee Sub Ell)

  Jim C.

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