These are the Exact symptoms I experienced w/ an 87 560 (same CIS-E), turned out to be a faulty KE control unit. Once the car was up to temp and the car went into open loop/regulated it lost it's mind.. The longer you drove the worse it got..no power, poping, burping, etc, etc.. You might try unplugging the KE..see what happens.

Jonathan

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Jonathan Hodgman
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