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E28 535i Mototronic problem

Help,  I have been trying to locate a gremlin causing my 85 535i to
surge particularly upon acceleration in second gear.  I wrote to Jim
Conforti and he indicates there is a lean surge in the car and he is
working on a chip solution.  I look forward to that fix.  However, when
snooping around last night I found something curious.  I disconnected
the oxygen sensor to read the value being put out and just happened to
attach the meter to the other lead and I found voltage!  The meter read
about .4 VAC and .4 VDC.  Is this normal?  Is this a reference voltage
the ECU uses to measure variation from the oxygen sensor or is my ECU
having a problem?  If anyone has tested the value from the ECU I would
appreciate the information.  Better yet does anyone have the information
and then FIXED it inside the ECU.  I read from someone a long time ago
that they were having performance problems and found a cold solder joint
in the ECU.  Anyone have any experience in trouble shooting what is
happening in the ECU.  

I would appreciate ANY information on this particularly frustrating
problem.

Car information 

85 535i

227K, 150K on factory rebuilt engine
No known defects
spark plugs read good
Jacobs Ignition (No appreciable difference in performance or mileage)
new fuel pressure regulator
new carbon canister for emission system

Thanks in advance
Stephen R. Barger
Intergraph Public Safety
srbarger@domain.elided
TEL 205-730-8152
FAX 205-730-8046