O2 sensor & 75 TS

[Oleg Solovianov <Oleg.Solovianov@cern.ch>]

Hello!

This is a very stupid question, and surely a FAQ, but I can't find the
damned thing (O2 sensor) in my non-cat '88 Alfa Romeo 75 2.0 TwinSpark...

The general sense is confused:

1. No catalytical converter -> no place to screw in the O2 sensor 
2. Engine management is Motronic ML 4.1 -> operates Ok without O2 sensor ?
3. Can't see any hanging wires...

I wanted to check the voltage, but no place to connect :) Just sometimes/some rpm ranges
the car is somewhat "sluggish"... Could be the engine temp. sensor too?
(at the back of the engine block)

Cheers,
        Oleg.

'88 75 2.0 TwinSpark (Rosso Alfa)

P.S. The car was bought in Netherlands by the PO. 
     Any word from NL digesters about cat/non-cat models?