Fiat stilo active (80)bhp ?

hi please can anyone help me i have a fiat stilo 1.9 jtd active (80)bhp.ive been told that i have the wrong m airflow on my car the one on my car at the moment is a bosch part 0280/218/120 and ive been told that i need a bosch part number 0281/002/308 but so many different garages have told me so many different things and now im lost my car is a september 2003 model hatchback 5 door please can anyone help me sort out this problem thankyou