E30 bad fuel pump

[E30325is@xxxxxxx]

i think i may have a faulty fuel transfer pump. every once in a while, i 
notice a slight hesitation at part throttle and full throttle, like the car 
has to catch its breath. this occurs about once every other week or so. other 
than that, the car runs excellent.  ive also noticed an audible 
"bzzzzzzzzzzz" from the engine compartment that wasn't there before. ive read 
that when the one in the tank goes, the main pump has to work harder to draw 
fuel from the tank, and that the loud buzzing is a symptom of an 
over-stressed main pump. the car is an early E30 325is, with both main and 
transfer fuel pumps. i suspect it's the one located in the gas tank. any way 
to test the fuel pumps to determine which one is the culprit? 

Kyle B.
NCC

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