Thought I would share my good luck. Engine light came on my 2007 Monte SS.
Went to Advance Auto to get the code. P0521 Oil sensor.
Located sensor easiler accessable near intake top of engine. Pulled it out sprayed with WD-40. Removed small screen where sensor screwed in and cleaned with WD40. Replaced all. disconnected negitive battery term for 30 minutes. Did oil and filter change.
IT WORKED!!!!! Engine light gone HURRAY!!!!
Now if I could only get the CV axle loose from the front passenger wheel hub...

 

Good job. Sometimes the axles require a little persuasion. PB Blaster soaked overnight and a 5 LB hammer should get that to move.