hi everyone

the problem started few days ago. Before that i just had a rough idle, but now car started to stall. Happened lots of times on the lights, when i drive slowly and now it starts dropping revs to zero when i drive, even at 60mph
it never stalled while driving but just had my revs going to zero and lights coming on, then pushed accelerator and car cought that up and was driving... ofcourse stalled on the next light..

CEL shows code 32- O2 sensor, but its what it s been showing me for last 8 months, even when before the whole rough idle problem started.

Any ideas, advises are appriciated

P.S. car acts different with 91,96 and 98 petrol.. never stalled with 98, stalled with 96 today and stalled many times on 91.

variable ignition timing? i mean ECU? or something else?

Thx