Hi!

Finally I seem to have found the major problem. I opened the OVP and found a broken solder joint. Actually it looked as if half of its connection would be intact. However, after soldering on the pin again, my idle was much smoother. Before, I had no ABS light on and I could measure the EHA current fluctuating, hence no hints towards a broken OVP.

Anyhow, I still have this issue with my EHA current during KonEoff. And it becomes even more strange. These were my readings so far:

day <10-20s >10-20s remarks
. 1 . 10 .... 20
. 2 . 10 .... 20 ... with eng off for a while
. 2 . 10 .... -7 ... eng off but directly after eng on
. 3 .. 6.5 .. 13 ... today
. 3 .. 6.5 .. -5 ... eng off but directly after eng on

10-20s means the current is different the first 10-20s after turning the key from thereafter. Day 1-3 are the different days I measured the current. Day 1 and 3, I used the same multimeter. I assume it to still work correctly as I measured a control current of -4 to +2mA during idle, today . The resistance of the EHA is a perfect 19.5 Ohm (as the reference).

So my idle has quite improved (econometer rotates about 5 DEG from time to time but the sparks are also not perfect) although I have an EHA current of only 13mA.

This leaves a few questions open:
1)Is it normal to have this step in the KonEoff EHA current at 10-20s?
2)What does it mean when the KonEoff EHA current behaves different when the engine ran directly before?
3)Is it critical to have only 13mA KonEoff?

AND
Steve got me so much into this closed loop thing that I wonder why my sparks have black sediments.
4)Is this only from the time when the O2 sensor is still too cold?
I would assume that in a warm system the KE should adjust the mixture in such a way that my sparks should stay clean.

5)If I got Steve right, all it takes to adjust the mixture is to receive an EHA current that equably fluctuates around 0mA and which should stay within +-3mA?!
6)In case I would have a different current at a stable 2000rpm and at idle, then I would have to search for an error in the system like an air leak, right?

Best, and thanks a lot
Tom