I just replaced the MAF sensor and still doing the same thing as before I changed it, do I need to clear or reset any codes or will it reset itself?

What is your question?

Changed the MAF but no change in the car, still dieing.. won't run past a few miles, could the new part be defective? Do I need to change/reset any codes?

What makes this problem better or worse?

Runs better when engine is cool, never runs hot

How long has your 2001 Pontiac Grand Am had this problem?

Every since we changed the head gasket.