afm interchangability (< is that a word?)

[bmw325csi]

does the airflow meter affect the cars overall speed and performance? The reason i asked is b/c my afm (091) recently took a crap on me so i replaced it with an earlier 083 from an 88 325i i believe and now it feels slower and not as responsive. Is the afm the culprit or should i look else where?

[Court M3]

yeah get an afm to match your car to fix it. Afms are not interchangeable IIRC