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Re[5]: ISV Questions, 1988 90q disinfo. correction

"Scott M." <scottmo@teleport.com> at INTERNET contributed the further helpful 
     The CIS-E III systems use a "differential pressure 
     regulator" on the side of the fuel distributor instead 
     of a "frequency valve" to adjust the fuel  mixture 
     (CO%). The differential pressure regulator can change 
     the mixture depending on how much current is applied 
     into this regulator from the ECU. I believe it is set 
     to be 0 mA at idle but the ECU can richen or lean the 
     mixture by applying + or - 10mA  using the close loop 
     system control with the signal from the O2 sensor. 
     This may be what was being done on your car when you 
     mentioned the 2.5mA adjustment. The ISV is a separate 
     thing all together, but the basic idle speed must be 
     correct before the idle mixture is adjusted.

This morning I contacted the mechanic and learned that indeed the meter was 
connected into the differential pressure regulator loop, not the ISV loop as I 
had thought.  I'm informed the 2.5 mA value can be found in the (a?) Bentley in 
a tune up section.  (I've ordered Probst.)  Sorry to start a thread down the 
wrong path.

***                 ...Kirby    (Kirby A. Smith)                 ***
***                      2 X 1988 90q                            ***
***              ksmith1@mailgw.sanders.lmco.com             ***
***              [=]   kirby.a.smith@lmco.com                    ***
***  Opinions expressed herein are entirely those of the author. ***