This circuit should represent a O2 lambda eliminator...
I have rebuild an original board because I destroyed a resistance and don't know with which to replace. I took a 1.1k Ohm.
The circuit seams to be a simple oscillator circuit.
I measured the capacities at the original board but they seams to be to small..
There was also a second op build in, but this op seams to be without any function for the simulated signal.