Hi everyone.

I have 1993 300E 2.8 with 160k miles on it. nearly year ago I started getting "hunting" in the idle.... started off very small, then before I decided to buy engine wiring harness and replace leaking head gasket, the idle oscillations were bigger.
Reading this forum I've discovered about harness and head gasket leak, so I bought harness for $750, gasket kit for $80 and replaced both.
While replacing I've found following:

The aluminum tume from EGR into Exhaust Manifold was plugged with sut. I had to get new tube because it was not possible to clean (break the sut) the old one. It was a consequence of the oil leaking into the cylinder number one (that specific location where it leaked) and then finding it's way into exhaust manifold.

Hoping that this was the problem all along to mu IDLE OSCILATION I was pretty confident that by the time we assemble this crap would be gone.

BUT IT DID NOT.... it still persists.

I start the car and it runs great once I dial the RPM to about 900 - 1000 ... but that will cause the "KICK" once you put it in "D" .... as soon as you dial that RPM down to 600 - 800 range --- the car will start going up and down in idle... sometimes it comes just to the point of suffocation, but then it strongly recovers like it's taking a big breath of air and keeps oscilating....

The next thing I'm suspicious of is the EGR valve itself and vacuum change-over valve ... maybe even idle control valve, but I have no idea where it is (ICV) ... because I have the CD manual for the car and it is pretty gloomy in the area of emissions if not even insuficient...

Please can enyone share if they had similar experience or if anyone can let me in on the papaer manual for this car (where available and how to get it) so I can diagnose certain components ... I'd be more than gratefull.

Thank you