PDA

View Full Version : Dying fuel pump?


Denton
08-24-2007, 08:31 AM
I can hear a loud hum from the right rear area of my E34 when it's on. Sounds identical to the fuel pumps of the '90s full-size Chevy trucks.

112k miles, not sure when the fuel filter was last changed but it's not the original. This summer it sat for three months driven about five times on 3/4 tank of Chevron premium.

Think it's a fuel pump going south? I have a 550-mile drive tomorrow and don't want to get stranded!

Help!
94_e34_525i
08-24-2007, 11:50 PM
I would really like a response to this too, because I have the same problem at first I thought it was going out but it still seems fine after about a year of noticing it, I sure as hell don't have 235 bucks for a new one.
Denton
08-26-2007, 03:25 PM
Update:

As far as acceleration lag, it doesn't lag any more than a heavy car with little torque and a slushbox in 100-degree heat.

The car hasn't died (yet) but is REALLY hard to start. If it sits for more than, say, 30 minutes, it takes three cranks and furious pumping of the gas pedal.

Still has a loud whine emanating from the right trunk area.

Taking it into the shop tomorrow.

One idea is that when it was in the shop in May, Dad let them do a fuel-cleaning process (which didn't involve a new fuel filter). Maybe that has something to do with it? Maybe mere coincidence...
bmwrp8
08-26-2007, 03:33 PM
checked the fuel pressure?
Milkboot
08-26-2007, 03:40 PM
I found out the loud humms are bad, whines, when they get real high pitched its also bad. It is easy to get to the pump and atleast take a look at it yourself.

I can tell you one thing, this is not what it is supposed to look like.

http://i3.photobucket.com/albums/y67/Milkboot/misc/crackedfuelpump.jpg
bmwrp8
08-26-2007, 03:43 PM
I found out the loud humms are bad, whines, when they get real high pitched its also bad. It is easy to get to the pump and atleast take a look at it yourself.

I can tell you one thing, this is not what it is supposed to look like.

http://i3.photobucket.com/albums/y67/Milkboot/misc/crackedfuelpump.jpg

that is EXACTLY what happened to my former fuel pump! I wonder how'd it do that to itself?
Denton
08-26-2007, 03:48 PM
Wow! How do I access the pump?
bmwrp8
08-26-2007, 03:52 PM
Wow! How do I access the pump?

here you go http://bmwe34.net/e34main/maintenance/engine/FuelPump.htm
Denton
08-26-2007, 03:54 PM
Thanks a ton!
Milkboot
08-26-2007, 03:56 PM
BMWRP8's post is the same thing I used to get to mine, just remeber to mark the fuel lines so you know where they go when you put it all back together!

Snakeyes and I forgot to do that and had to match up the marks made by the fuel hose clamps hahah, luckly there were two differnt kinds on there.
Denton
08-26-2007, 03:58 PM
Great, thanks! I'm sure it will work...that was a good writeup.