E28: Rough running above 2000 RPM

[ASparks106@xxxxxxx]

I have an '82 528e that I have been wrestling with for several weeks now and
am in need of ideas.  I presently have the car at a very reputable BMW repair
only shop in Augusta, GA and they are also stumped.
The symptoms: Starts fine, idles fine, runs great up to 2000 rpm, then cuts
out and has basically no power.  Gas mileage is awful.
What we have examined so far: Fuel pressure and flow rate - OK. Coil, plugs,
wires, condensor, rotor - Checked all OK.  Air mass flow meter - put in good
one to test - No improvement.  Motronic brain - put in a good one to test - no
improvement.  Fuel injectors - put in good ones to try - no improvement.
Vacuum leaks - None.  Catalytic convertor - checked but not stopped up.  O2
sensor - Checked OK.  Speed sensor and TDC sensor - checked OK, but could be
going bad at higher rpm; will replace next and then try.  Throttle switch -
checked OK.
HELP!  What else could be the problem?  I have pretty much run out of options.
Andy Sparks
Thomson, GA
'82 528e

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