1badpontiac

I have been having problems with my car loading up, and not having good throttle response. The car was tuned by rp motorsports in atlanta, i havent had a minutes trouble out of it until now.it is not the tune, i put it on the scanner, and i got a maf sensor code. I have a salvage yard, so i got a maf sensor off of a 98 truck. half of the numbers match, i put it on and it seems to have helped the car on the loading up, and has better throttle response than with the bad one, but doesnt seem to run as good as it used too. My question is will putting the truck sensor on effect the tuning, and is it the same. I just need to get it running like it used too.