e46 325i cranks but wont start and buzzing sound coming from throttle body area

I have a 04 325i with 130,000km on it and a ll of a sudden it stopped starting. the engine cranks but does not fire. When the key is fully engaged there is a continuous buzzing coming from the under or around the intake side of the engine bay. I cranked the car to see if any codes would come up but no check engine lights came on. I also put a little throttle body cleaner wile it was cranking and it fired right up. I guess what I'm asking is what steps should i take to narrow it down what's wrong. and if it is the fuel pump would i need to replace the whole thing or just a specific part. Thank you all in advance and hope i can get the car running again with my own two hands.

e46 325i cranks but wont start and buzzing sound coming from throttle body area