How many O2 sensors does a 1997 Saturn Sl1 have and where are they located?

Answer 1

The Oxygen sensor that typically on MOST vehicles is the one closest to the heat of the exhaust. Since the SL1 is a 4 cylinder engine with a single exhaust manifold, check (or replace) the FRONT oxygen sensor, which is in the exhaust manifold, just above the "headpipe". It looks a little like a sparkplug, and should be the only thing in the exhaust manifold that has a wire connected.