The CPS is always in the loop. To prove it (to myself) I just went out and started it, then pulled the CPS plug from the EZL and it instantly shut off, just like turning off the key.

no, that's not the crankshaft position sensor you are talking about... it's something but not that.....

the CPS in not in the loop at all once the engine is fired and running.
The CPS' job is simply to tell the ECU where TDC is and then hand the rest off to the ECU once confirmed...that's it...from that point forward the ECU runs the show and CPS just sits around waiting for the next restart...that's it....I would be happy to elaborate

I unplugged the connection at the upper left coaxial-looking port of the EZL.
It is the crankshaft position sensor connection.

More details in this other thread:
http://www.peachparts.com/shopforum/tech-help/263045-89-300e-crank-sensor-help.html#post2313926

Yes, that is the crank sensor connection to the EZL, and you are unfortunately getting unreliable advice about it.

__________________
1988 California version 260E (W124)
Anthracite Grey/Palomino
Owned since new and still going strong and smooth
MBCA member

Past Mercedes-Benz:
1986 190E Baby Benz
1967 230 Inherited from mom when she downsized
1959 220S Introduced me to the joys of keepin' 'em goin'

There are only 10 kinds of people in the world--those who understand binary and those who don't