Replace fuel pump?

[tgrandahl]

Ok, not sure if this has been discussed before but i have been searching awhile now. I have a 95 525 and live in rochester NY most of the winter when i start the car on a cold morning it usually takes longer to start, lets say 10 to 15 cranks. When it does start and i sit there shivering i can hear a "mrrrrrrr" sound coming from the rear of the car. Its sounds like something between a electric shaver and a fish tank pump(the motor not the water). This noise disappears once the car has run for a couple minutes and starts to warm up.

I have also noticed that the performance of the car is affected by how much gas is in the tank. On a warm day if i have half a tank of gas and stop to fill the tank when i start the car again not only will it start on the second crank as apposed to the fifth or so, but it feels somewhat more responsive. As if the lubrication from the fuel is helping the pump?

I also find it hard to feel any more power from the engine between 2/3 and full throttle. At close to 200Kmi i have been thinking about replacing the fuel pump / filter. Good or bad idea? any other suggestions? is there a tap in the fuel system for checking the fuel pressure?

Thanks
Tyler

[Blitzkrieg Bob]

with a filter, and a fuel additive (alcohol) to remove any water.

You may have water in the tank, and a dirty filter.

[BillionPa]

low sulfur fuel doesnt have much lubrication

change the filter, then add 6oz of seafoam and 4oz of 2 cycle oil to a full tank of gas, preferably ethanol free gas if you can get it. also see if you can fill up early in the morning, before 10am.

my fuel pump was on the verge of failure and very loud, and adding fuel lubricant to every tank shut it the hell up over about 1500 miles of use. i am gonna replace the pump this summer along with the sending unit and all the fuel lines as preventative measure though, hopefully with a new radiator and water pump as well.

[bmwrp8]

before changing you fuel pump id suggest that you change your fuel filter then do a pressure test.