Cracked Fuel Pump - BMW Forum

DonJ · 08-20-2009, 02:12 PM

Ever see a fuel pump do this?
<see attachments>
Sorry one is a bit blurry - my batteries died before I could ge a better pic.

This came out of my 1991 535i.

I replaced the pump yesterday and this is how it looked when I pulled it out.
This might very well be the reason for the intermittent starting problems I was experiencing - especially when the weather cooled down a bit (I have an earlier post on this forum).

I'll finish up tonight working on it and I'll run it for a few days and see what happens.

The pump is very easy to replace but I was also in the middle of changing out the Crank Position Sensor and I don't have the cooling fan put back on yet.

darkhorse737 · 08-20-2009, 02:22 PM

just out of curiosity.... do you have subwoofers in your trunk??

DonJ · 08-20-2009, 03:00 PM

No I sure don't.
Stock radio system and speakers. The only stereo equipment in the trunk is the 6 CD Changer. That and a bunch of junk :-)

Torque · 08-20-2009, 03:40 PM

Is all of that plastic surround still in one piece? Maybe it was bouncing around and self-destructed?

We changed the pump in my dads 535i last weekend and the thing wasn't even clipped in.

DonJ · 08-20-2009, 04:09 PM

Nope - it was all snug and secure inside the plastic housing. I had to push on the latches on both sides to get it out of the housing.

I did replace the in-line filter as well as the pump.
I'm wondering if the filter was getting clogged and it over pressureized. But that seems like a lot of pressure to do damage like that.