1985 380SE air flow meter mixture adjustment
 

Which direction should this be turned to lean the mixture?

Counterclockwise to lean the base setting, clockwise to richen.
Of course, you understand that when the engine goes into closed loop, the O2 sensor will adjust the EHA to obtain an optimum mixture (if the base airflow meter setting is not too far off).

What are your issues? What are you hoping to fix or improve?

DG

I installed a used fuel distributor on it. It hadn't run for several years because it wouldn't start. When I last drove it I would stop and get gas at just about anywhere so I'm sure it had ethanol in the fuel.

I pumped the tank dry using the fuel pump and put ~ 3 gals of fresh dino gas in it. It's still a little hard to start now and idles rough. It hesitates on acceleration while in park. I haven't tried a road test or run enough gas through it to know if the moisture is cleared from the lines and such. I plan on doing that before I dally with the idle mixture.

I want advice on this and appreciate any you'd offer.

Although the 1985 380 does have O2 sensing and a feedback circuit, it does not have an EHA (which is part of the third generation of K-Jetronic, aka, KE). 1985 is in the second generation (often referred to as K-Lambda), and is still equipped with a control pressure regulator (aka, WUR). The fine, feedback mixture control is via a frequency valve and its controller.

As the OP works thru the problems, both the WUR and the frequency valve may become candidates for investigation.

Were there ever any third gen 380's? (or were they replaced by 420) and would a fuel cleaner be advisable here. Which ones?

third gen
 

third generation is bosch KE3-jetronic CIS-e fuel injection was used from around 1986 or 87 till 1991 on a variety of different vehicles like rolls royce and Ferrari even lamborhgini as well as Mercedes

My thanks to each of you for your input. I started it late yesterday after replacing a leaking water hose. It's still a little harder to start than it should be but it was easier than before. It also ran a little smoother and even fairly smooth but not like a V8 should. I still haven't burnt the oil off the exhaust manifolds yet so I'm not close to really trying it out.

I'm about settled on the fact that it's still trying to pass some bad gas. You know how troublesome that can be.

I've got to change the PS pump filter then we'll take a little trip down the mountain for a bath at the local car wash. I'll report back then.

Let me know how this turns out... I'm having a similar issue with my 380 as well