Because with the CO pot I can't get the AFR richer, I've adjusted the fuel pressure regulator til got the correct AFR. (without a pressure gauge... ye, I know it's not tha best to adjust it by "feeling"... )
BUT!
The AFR is now ok, the car is better than ever, I hope it's not just placebo


Another thing is the mk4 factory trip computer shows nearly the double of the real values. Finaly got a scope from a friend, so we played a little bit.
The FRST EEC IV (OFAC) and the Escort mk4 EEC gives different signal on pin 17 (the fuel flow signal), not just the lenght but the timing.

Saidly I've only made a video of our first test, the scope test: playing with the VSS: