I have been reading this through couple of posts but am still skeptical. Is it the c-clip?Some people lost a plastic piece of the top of the by-pass and claim they killed their engine. I want to fix this oil light asap. I have changed to proper mini filter with hopes of that changing but it still illuminates. What would happen if we were just to remove the entire piece? Its stuck open anyway when the filter element is in there.

 

Are you talking about the plastic piece inside the oil filter housing?
If so, you should replace both the oil filter housing and the cap with the newer version. Filters for the old version are no longer available, so you are technically using the "wrong" filter.

 

Yes they are. I just picked one up from a Mini dealer via my VIN number.