02 Impala running poorly, CEL is on
 

My mom's 2002 impala with 67k has started running very poorly and dies frequently while driving. I checked the plugs/wires/coils and they all seem to be fine. It is throwing a CEL for "Fuel system lean" so i figured it could be the pump, fliter, FPR, or injectors. The car feels extremely restriced and it is difficult to get up hills and up to highway speeds. I thought that maybe the cat was clogged, but would that cause the lean CEL?
Any recommendations on where to start? Are there any common problems with these cars related to this? Any input would be greatly appreciated. Thanks.

RE: 02 Impala running poorly, CEL is on
 

Go to autozone and get a scan

RE: 02 Impala running poorly, CEL is on
 

I already did. Thats where i got the "fuel system lean" from.I put in a new fuel filter, and the car runs a tiny bit better. Its not dying anymore, but it still feels extremely restricted and is almost impossible to get over 40mph, and struggles to get up steep hills.