Crankcase position sensor

(1997 camaro 3.8 v6 auto)
I recently changed the crankcase position sensor, and one of my questions is: do I need to take the car in to have the relearn procedure done or not.
Here is a little background on the problem, leaking water and overheating-my father-in-law changed the timing chain cover gasket and fixed the leak. But now the thing misses smells like gas at idle, won't accelerate-stumbles- general does not run well at all. He said it just needs the plugs changed and new wires. So I changed the crankcase position sensor out and guess what-it did not help. I figured it was running fine before he took the sensor off to replace gasket so for me that was a logical place to start. P.S. I checked the codes and crankcase position sensor came up along with intake air sensor and a bad cat-converter. Any ideas would help alot.