What is this on 88 560sl
 

On injector pump and leaking drops of gas. Thanks in advance. Can’t load photo site won’t allow temp disabled. It is on the side of injector pump, it is plastic and has wires coming out of it. Merry Christmas

Red-
Not injector pump at all; it is the Fuel Distributor (FD). The electric high pressure fuel pumps are in the back of the car.

Blue-
The Electro-Hydraulic Actuator (EHA). It controls mixture in response to signals from the O2 sensor.

Sounds like EHA Valve...

THANKS You guys nailed it, I ordered the two $6.00 O-Rings instead of the $365.00 valve along with 2 Engine Air Distribution Hoses. I'm hoping that will O-Ring solve the drip and the Air hoses solve the rough low idle and stall at stop signs.

On that year you might want to consider a spare ICM, only about 30$ chinese, instead of $650 original Bosch if you could even find it. Those things start being iffy then suddenly you have nothing - ever again. One way to kill the original unit is to high pressure spray the thermal paste out from behind it. Have you washed the engine bay? It fries the interior bits as that huge aluminum case is relying on dissipating heat to the body as designed.

The leak may not be caused by the O-rings (hopefully it will). There's a very small weep-hole on the EHA housing that signals internal failure of the EHA. I've found this to be the problem more often than not.....

Yup.

I've found the EHA to fail more often than the o-rings....