I swapped ecu's with one in a breakers yard, no difference. I then realised that I wasn't using the ammeter function correctly, I plugged the wire into the wrong port . My EHA valve is enriching the mixture on blipping the throttle. I didn't see the +15ma change but I tested the car hot.
I decided to test my engine compressions and I got:

13 bar
13 bar
13 bar
12.5 bar
13.5 bar
12 bar

Cylinder 5 & 6 are just within the mercedes 1.5 bar tolerence in their literature. The compressions are slightly higher than 300E compressions due to Brabus raising the compression ratio. Cylinder 6 is leaking slightly from the rings. I introduced a teaspoon of oil and then read 13 bars from it's compression test. However I don't think my compressions should be giving me the problems I am seeing at the moment?
The crankshaft position could also apparently be causing this? I have never seen this mentioned on any forums as being such a cure.