85 528e running rich update

[PandTHayes@xxxxxx]

Here is some more info on the problem with the 528. Following several 
sugestions from digest members, I have done the following with no change.  I 
switched the fuel pressure regulator with the one from my 535, no change.  
The car runs the same with the idel valve conected or disconected.  The valve 
does hum when conected.  I will try swapping that  with the one from my 535 
tomorrow.  I replaced the O2 sensor with the one from a parts car, no change. 
 A sugestion was made that it could be a temp sensor.  My car has what would 
seem to be three sensors in the thremostat housing, which one controls the 
ecu loop?  The problem with this car has me very confused.  Even in limp home 
mode I have never seen a car run this rich.   The car simply will not run 
below 3000 rpm. I have considered that I may have a intake leak some where 
causing the ecu to dump more fuel.  However if this was the case disconecting 
the O2 should help lean it out, correct?   Any help greatly apreciated.
Patrick Hayes
Greensboro NC
87 535is
85 528e
88 jetta

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