E30 Zone

Hi folks
My fuel pump is making an awful whining noise and I want to change it before it packs in an leaves me stranded somewhere. Ive been looking all over the place to find a fuel pump on the net but can't find anything specific. Could anyone point me in the right direction please? Are all E30s the same fuel pumps? its the one under the rear passenger seat I want to change.

cheers in advance

Early E30s have a pump that is external to the tank, and mounted in front of the left rear wheel.
Your iS will have a more modern pump inside the tank.
There are two versions of the in tank pump assembly - one for 55 litre tanks and one for the 62 litre version, although the basic pump is identical, and quite easy to change.
The difference between the two assemblies is that the 55 litre version, which you should have, has a stub pipe on the top for the fuel return pipe from the fuel rail, as well as the stub pipe feeding fuel out. The 62 litre pump has this return stub cut flush with the top of the assembly and blanked off.
A 62 litre pump can be used in a 55 litre tank by blanking off the second pipe, but you will need the two pipe version.
Check that the tank hasn't been dented upwards under the fuel pump, as this will result in a lot of pump noise if the tank bottom is touching the pump.