Make sure you don't have any vacuum leaks, as they can also cause that same fault code.
With that fault code, it will either be a faulty O2 sensor heater relay, not allowing the O2 to heat up at idle (making it give false readings), or the O2 sensor itself could be faulty. Try this:
- disconnect the battery so the DME loses it's memory/adaption
- reconnect the battery
- disconnect the O2 sensor (leave it disconnected)
- start the car and see how it runs (you'll probably have a CEL from the O2 being disconnected)
If the car runs smooth and trouble free, then it's the O2 sensor (or relay) at fault. If it still runs weird, then it's something else (vacuum leak, bad coil, faulty idle speed motor, etc.).