E30 Fuel Pump

[Coffee&Doughnut 0]

Hi, My 88 320i wont start, not getting any fuel but ignition system seems Ok, fuel pump relay and fuse seem ok too.

I am confused about E30 fuel pumps from what I can gather some have 1 in the tank and 1 under the seat, some 2

in the tank and some just the 1. I dont know for sure yet if I have to replace the pump but if I do I gotta do it before rego, soon.

can anyone advise me, thanks

[gmccormack 0]

Some have only one pump in the tank, accessed from under the rear seat. Some have only one mounted in front of the left rear tyre. Some have two, one in the tank and one in front of the tyre. All the pumps are noisy, so you should be able to hear them if they are running.

[Silver Fox 43]

They only have one or the other according to the restoration bible, have a look under the body behind the back door by the rear subframe mount on the passengers side, if you have the external one that's where it is, being an 88, it should be internal, and you should be able to hear it humming when then keys turned over. They changed around the time your car was made, so if you lift the rear seat base out and undo the plate behind the drivers seat under where you took the base from, you should see the top of your fuel tank, and be able to hear when the pumps running, makes quite a noise. One way to check if it's working is to undo the fuel line where in comes into the engine bay, feed the pipe into a plastic bottle and turn the motor over to see if you have fuel being pumped thru, remember it's very flammable, and be careful.

Edited March 26, 2007 by Silver Fox

[gmccormack 0]

They only have one or the other according to the restoration bible,

Mine has two, as did one of my parts cars. The intank pump in the twin pump cars is not a high pressure EFI pump, it only keeps the external pump primed. The car will run without the internal pump working but the external pump becomes even louder and the external pumps life is shortened if the intank pump is not working properly.

[Coffee&Doughnut 0]

I wont be able to check till tommorrow, but suppose I have the internal pump under the back seat, would that mean I would have the second pump at the rear wheel as well? And would I have to replace both pumps or could i just replace the in-tank one with one of these....?

http://cgi.ebay.com/ebaymotors/New-BMW-E30...sspagenameZWD1V

Thank for your help, just trying to get an idea what parts I may need.

[will 169]

Graeme is right, there are 3 options, the Bentley manual clearly describes them. I have found several errors in the e30 restoration bible based on my own experience and cross-referencing other manuals. I have an 89 320 with an external main pump and a 91 318 also with an external main pump, but an 88 320 with an internal main pump.

Don't just replace pumps, get a pressure check done first. If you have a lift pump in the tank, it should pump at 0.3bar. the main pumps, whether inside the tank or under the passenger side sill, should pump at 3bar, give or take a bit in both cases.

The lift pump will only be used in conjunction with the external pump, and is not really necessary, but it does help keep the main pump healthy.

Check your fuel filter at the same time, could be blocked.

Will

Edited March 26, 2007 by will

[Coffee&Doughnut 0]

Ok looks as though the pre/pickup pump is in the tank, and I got the external one rear passenger side.

I only replaced the fuel filter a week ago. So its getting checked at the mechanic I didnt feel like getting doused in petrol again this week after replacing the filter, actually it was the E32 that doused me in petrol the E30 was ok.

[Coffee&Doughnut 0]

All sorted, turns out the fuel pump was ok, the problem was the 7 pin connector under the throttle body had some broken wires and there was no signal to the fuel injectors. I rekon it was only just hanging in there as I had an intermitant problem with the engine shutting down without warning. Running better now than before. I only have the Haynes manual which is not very dependable. Thanks for the help everyone.

[IPLEZR 0]

i have a brand new internal pump 4 a e30 320i, just got it bout 2 months b4 doing my conversion, replaced with a 00hp walbro pump so its just sitting round if any1 is interested?