Which 02 sensor (1.3L)

When a 97 metro 1.3 shows an O2 code, is it the upstream (near manifold) or downstream one (near converter), which is causing the trouble?

The upstream one

Thanks,
the exact code said PO 141 "Bank 1 Sensor 2" O2 sensor heater circuit malfunction?

Then there was a 0400 EGR Flow malfunction, but that one was reset and did not reoccur

So is it still the upstream one?
Thanks again
FGlass

Sensor 2 is the downstream one(after the catalytic converter). "bank 1 Sensor 2" is the generic interpretation of the OBD2 code. In the case of the Metro bank 1 has no meaning.

Sounds like the heater in the sensor has burned out. You can check it for continuity with a multimeter.

Bit suprised about the EGR code - I have a 2000 1.3L and these do not have EGR. Maybe they were designed out in the later models.

BTW the code is actually P0141 - not PO141 (zero next to the P)