E30 engine problems

[Keith Turner <kturner@xxxxxxxxxxxxx>]

 A friend is having problems with his 87 325is.  It will run fine, then run
rough and occasionally stumble/hesitate under acceleration.  Using a
different ECU (from a junkyard) made no difference.  The plugs, plug wires,
fuel filter and O2 sensor have been recently replaced.  The check engine
light stays on constantly and does not flash a code when the key is turned
to on. Anyone have any suggestions?

Thanks,
Keith Turner

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