I just replaced my mass air sensor and now with it in there the car is stalling

i got it on ebay and the reason I changed it was a check engine light was on and checked codes and that told me it was the mass air sensor . I just went out side and ran the engine with the mass air flow sensor not conected and ran great so discounected the battery and conected the mass air flow sensor and drove it better but didnt go to far

The code is for the system or circuit affected , NOT necessarily the part. I agree with globalhelper about the part(s) , OEM is usually best.

any ideas what it maybe Im a little mested up now that i put the old one back in and didnt stall and when i put new one in it it stalls out RR

YOU BOUGHT IT ON E BAY WOW REALLY IT COULD BE THE SENSOR OR THE CIRCUIT. THE DOESN"T ALWAYS MEAN CHANGE THIS PART, THATS WHY WE GET THE BIG BUCKS WE DIAG THE CIRCUIT