BMW Repair: Emissions fault, bmw 316se, lambda sensor

Question
BMW 316se, 2000 E46
Emissions fault light continually on - local garage have changed lambda sensor, fuel filter, spark plugs all to no avail.
After they reset the fault it could be ok for up to a week then reappears.

Answer
Craig, What is are the Faults that are stored in the DME (engine computer). Those items that were changed are great maintenance items to replace on cars with over 100k miles. So even if it didn't fix the problem don't feel bad even though it is frustrating not to have the problem fixed. I need to know those faults. I also need to know when the light turns on. What other symptoms the car exibits. Misfiring? Surging? Also I have never heard of a 316se. Is it a Euro market car. I know it is not a U.S. Car. Respond to the post once you have this info.
-Evan