Just wanted to share an experience I had so it may help someone else in the future. Not this applies to fuel injection only.
if you follow my post here, http://www.redpepper...showtopic=59547 , you will see I had an spin at the track. Since then I noticed the fuel pump was very loud and the car is not running as well as it was before the spin. My thinking is perhaps I stirred up junk in the tank and plugged the filter.
My setup is an aftermarket fuel pump in the stock location with a filter between the tank and the pump to keep junk from hurting the pump. If you have a stock fuel pump you have a small screen in the end of the pump to do the same thing.
I pulled the filter apart and sure enough it was full of junk. Cleaned out the filter and housing, mine is reusable, and sure enough the pump is quite again.
so if you suddenly are noticing a louder than normal fuel pump your pre filter may be causing the pump to have to work harder and it need to be cleaned. I also drained out a few gallons of gas from the tank and found the same black junk came out.