"Super eta" with 9/1987 Build date

Car was bought as a non-running vehicle, but only a few minor items were not connected under the hood (per seller for an unknown reason).

There is no start when the engine turns over, and there is NO SPARK.

The coil and injectors do not "pulse" electrically on rotation.

Checked the CPS and it has normal coil resistance of 545 ohms, and when engine spins the CPS produces a nice 4v peak-to-peak sine wave (unplugged from harness). I couldn't find the factory specs for voltage output of the CPS, but 4 v p-p seemed reasonable to me, and this CPS WILL start another vehicle it was substituted into for testing, however.

I checked all DME pins at the ECU connector to where they are supposed to connect at the end of the harness, and each had perfect continuity to its assigned wire under the hood. I used the "BMW No Start Guide" posted 3/4/16 by Dan Downey at https://www.eeuroparts.com/blog/6018...o-start-guide/ as well as several other reference papers I searched and followed.

The ONLY point in the troubleshooting guide that is suspect is that they warn that the Main Relay be an OEM one, and not a generic one. The one in this car has 30, 87, 87a plus the 85/86 coil contacts, so should work, and looks newish and activates properly when the key is turned on. The coil (a brand new one) + terminal is receiving battery voltage with the ignition on and in start, but putting an oscilloscope across the coil terminals at start shows no pulsation as one would have if the DME was grounding the - terminal to generate a spark.

The only pins I did not verify were the ones (#8 and #31) that say they are "Cylinder ID Input" as I wasn't sure what those are, but later I realized maybe they meant the connector that mates to the loop of wire around #6 Spark Plug wire at the distributor? Of course, in a normal start sequence, that device would not provide a signal to the DME until AFTER the car was producing a spark, anyway, so it should not be a factor in starting. I went back and checked the resistance of that loop at its connector, and it was 0.4 ohm, which seems reasonable.

I have 2 DME computers, the original furnished with the car (ending in #154), and a "spare" (ending in #525) obtained elsewhere, and that I was told would work with the vehicle (It was on a ECU interchange list), but I have no positive proof that this interchange is accurate. Given that the engine stopped running prior to my acquisition, I also cannot rule out that the original DME is "good."

Any suggestions most welcome!!