Fuel pump replacement

[Brianmoooore]

Well .... if it's running, all well and good, but an airlock in a fuel line is impossible!

That's with everything in full working order of course.
I suppose that if the fuel return to the tank were blocked fuel wouldn't get as far as the engine, so disconnect the return hose from the fuel pressure regulator, and check that you can blow bubbles in the tank through it.

[jcm325]

The return hose from the fpr was the one I had disconnected only because it was easier!!! I wonder if bits of the blocked filter could have caused any issues?

[Brianmoooore]

When the pump was running, was the fuel coming from the disconnected hose or the pressure regulator?

[jcm325]

It was coming out of the fpr....

[Brianmoooore]

It was coming out of the fpr....

That's where it should be coming from - for a moment you had me thinking that somehow the engine was running with the fuel hoses the wrong way around.
Check that you can blow through this hose, back into the tank.

[jcm325]

Checked the return line today and it's clear car started again no problem and drove well no signs of fuel starvation...
Many thanks for your help Brian no doubt I'll need it again!!!!

[Brianmoooore]

I advise you to keep tools in the car to enable you to remove the cover above the fuel pump and something to give the top of the pump a good thump, in case this is the start of a failing fuel pump, and it decides to quit while out on the road.

[Cyant1fical]

Mine done this and in my experience it was one of the most simple yet frustrating jobs I’ve done on the e30 so far... I was towed to the garage towed home wrong fuel pump came had to buy another and couldn’t get a refund on the one I had originally purchased... I thought my stereo was on a constant live killing my battery and everything, now I drive round with an extra fuel pump just in bloody case and about 100,000 fuses and few relays in a little bag haha, if I remember correctly after much diagnosis thinking it was god knows what I changed..

Fuel pump but not fuel sender
Fuses upped to the next which I think is 10 or 15
Changed crank shaft sensor
Changed spark plugs

I got it going in the end but this is temporary anyway as my next plan is an engine swap as my current is looking toward the end of its life if I’m honest

[TriggerFish]

I know this petered off into something else, but the eBay fuel pumps were touched on briefly (https://www.ebay.co.uk/itm/FUEL-FEED-UN ... 2749.l2649).

I ordered one of these, and my thoughts are limited only to fitting/starting/parking the car. I've not taken it on a run to see if it stops my fuel starvation problem with less than 1/4 - 1/2 a tank.

It seems the right size though (unlike the generic eBay one that claimed to be for an E30...):



That's a crappy photo, but the top pump is the OEM holder with a generic pump. You can see that the little filter bag has to sit above the top of the brass assembly, meaning it's way off the bottom of the fuel tank, leading to problems. The new/one from the link above has a frame that's the same size, and the filter bag is in the right place, so as long as the pump itself holds up, then it should be good.

However, the four studs for the fuel level sensor/sender were in the wrong place - I had to open up the holes in the sender to 6.5mm, which then let it go back. I'd guess they were 5 or 5.5mm to start with, as I went to 6mm to start, but that wasn't enough. My phone, and SLR, both ran out of battery, so I didn't get a photo of this.

Once fitted, it fired right up after the usual length of cranking.