Fuel Pump Noise

[Gdub]

Just this morning I began to hear an intermittent whine (repeats whining for a half a second, no whine for half a second) from the back of my car. I hear the whine while the engine is running (stopped or driving). I opened my trunk and listened and the noise was the loudest right above the fuel pump access hole. My fuel economy is at about 13mpg and car idles at little ruff and will sometimes completely lose power (but not stall) for brief moments during acceleration. Last week i had the same problem but i didnt have the whining noise, and I filled up on gas and the problem went away. I ran STP fuel treatment figuring that i had some junk in my fuel lines. Is this whine coming from my Fuel Pump/Fuel Level Sender area calling for a new Fuel Pump? Lowell? Winfred?

[Jr ///M5]

While the fuel pumps on the 5 series are rather robust, it might be worth replacing your fuel filter first before you plop down a couple hundred for a new pump. You would have to change the filter anyway after a pump replacement. The idea here is that maybe your filter is starting to get dirty and is placing the pump under load causing the noise. There are pumps that constantly make noise (steady whine) and are perfectly fine, just the nature of them. But if you notice it getting louder and the steady noise changing, the fuel pump relay could be causing some problems also.

In short, start with replacing the fuel pump relay and the fuel filter before condeming the pump. You can verify that the pump is producing adequate pressure by doing a pressure test after the filter is replaced. Fuel pumps are cooled by the fuel in the tank, so if your tank was near empty, it would explain a pump making more noise. Try not to let the tank get below 1/4, especially on aging pumps.

[Gdub]

I replaced the fuel filter a couple weeks ago and yes i put it on in the right direction. I have not checked the relay will do so. I never let my tank go below 1/4 tank. The pump did not used to make this noise thats I was wondering if it was getting bad or something else was causing the noise.