where is the fuel pump?
Probably in the fuel tank.
The E30 fuel pump is sitting in the fuel tank. you should be able to access it from under the rear seat. Check out http://www.ehow.com/how_6645968_change-fuel-pump-bmw-e30.html
at side of the car
There are two fuel pumps. There is a low pressure pump that hangs into the fuel tank. It is located under the back seat beneath an access panel. This one is easy to replace. The second is a high pressure pump and has two pressure dampers close to it on the driver's side along the frame. Follow the fuel lines and you should find it . This one can be difficult to change and require replacing the special vibration damper mounting bolts for the fuel pump mounting bracket. Just getting the fuel pump out of the mounting bracket may require cutting off the bolts that hold the mounting bracket around the fuel pump. If you have the right tools or the bolts aren't all rusted you should be able to do it, just be ready to cut/replace the fuel hoses so you can take the whole mounting bracket out which will make it much easier to work with on the bench.
Did u replaced the pump? Where did u buy it from ? What was the symptoms ur car was doing?
Looking for a Used 3 Series in your area?
CarGurus has 40,587 nationwide 3 Series listings starting at $1,350.
Search BMW 3 Series Questions
BMW 3 Series Experts