Feul pump relay faulty. could be something else?

[brightyboy]

suffered from a faulty feul pump relay the other day (saved by the RAC man) & last night i had 2 leave her in work as she wouldn't start again. I used the relay that controls the sunroof instead as a tempory measure but i think its packed in again? now she is stuck 12 miles down the road,how much is a feul pump relay and where can i get one in south wales A.S.A.P.
Or a good mechanic near Newport.

[Andy_magic]

You can temporarily bridge the relay conections with a wire link, I'm not sure of the exact pins though.

[Brianmoooore]

Bridge pins 30 and 87 of the relay base. In an E34 I stripped a while ago, I found a couple of yellow relay shaped boxes with just two pins, 30 and 87. All that is inside them is a link between the two pins, so now one of these lives inside the fusebox cover of my E30s.
Might be the relay, but my money's on the pump itself, I'm afraid.
Fuel pump fuse is 11, and is the last thing before the pump, after the relay.
Check for 12V+ at the fuse(you can get a probe on the actual fusewire if it's an OE fuse) when the engine is being cranked.

[brightyboy]

Thanks i bridged the pins,she's still not turning over.I'm picking up a new relay in the morning from bmw but i'm thinking it may be the pump aswell. a friend of mine said there is another relay im supposed to bridge,something to do with the ECU telling the car to stop pumping the fuel in the event of a crash,how true this is i do not know.maybe i should just join the RAC

[Andy_magic]

I'm assuming your car is a motronic, the fuel pump only runs on starter and then when the engine is running via a signal from the ECU.

I think the earlier jetronic cars run the pump when cranking and when receiving pulse signals from the ignition system.

I could be wrong though.

[Brianmoooore]

Thanks i bridged the pins,she's still not turning over.I'm picking up a new relay in the morning from bmw but i'm thinking it may be the pump aswell. a friend of mine said there is another relay im supposed to bridge,something to do with the ECU telling the car to stop pumping the fuel in the event of a crash,how true this is i do not know.maybe i should just join the RAC

Don't throw money away changing parts at random. Test and diagnosis is the way to go. Don't join the RAC either. In my experience of them, if you aren't better at sorting E30s than them, then you shouldn't be allowed a driving licence!
Have you checked for 12V at the fuse?
As a more conclusive alternative, connect a piece of wire to the 12V + terminal of the battery, remove fuse 11, and push the bared other end of the wire into the fuse socket nearest the outside of the box. This connects power directly to the fuel pump. If you listen near the tank you should be able to hear it whining, and if you turn the key the car should start and run.
If it doesn't , you almost certainly have a dud fuel pump. (Or the problem is nothing to do with the fuel system, of course)

[BaggedE30]

ive got a similiar problem...my car was running fine..i then stopped it and started it and it didnt start, so i had to get towed home
following morning i mucked about with the relays, didnt change nuffin but i tried briding the pins etc, then the car started
drove it for a while stopped it, and again it wouldnt start, but i have 12V at fuse 11 when crankin it even tho it dont start
i didnt tihnk it would be the fuel pump because once started the car runs fine? it just has a problem starting in the first place..could still still be the fuel pump?

[Brianmoooore]

Failing fuel pumps don't just give up. They develop a habit of stopping suddenly at inconvenient moments.
Last one I had fail on me, (the subject of a very long post back in August), it would run OK, except on the reduced voltage when cranking the engine.
One before that had no problem starting the car, but stranded me three times in the same village about four miles away.

[BaggedE30]

hmm, my voltage only drops to 11.5 ish when i start the car though and my sound system draws it just as low as this and i have no problems? it did it again just now..it didnt start at the top o the road..i walked home and left it two hours went back up there and it started first time? but then there was voltage at fuse 11 so i geuss it MUST be the fuel pump?

[BaggedE30]

anyone?

[brightyboy]

rang German Swedish French (GSF) IN Cardiff the ordered me a relay Ԛ£23 ,went to pick it up next day and the guy behind the counter had ordered me the wrong one,no luck, so i went down to Newport and into RYDALE B.M.W (by the docks) they had the relay there Ԛ£5 job done, The E30 is alive and kicking thanx for everyones help, (dont rule out BMW Dealerships for parts,they know what they are talking about) The also had a new Ԛ£75,000 alpina 7 series on cream leather & huge rims,you would have to remorgage house 2 buy 1

[brightyboy]

anyone?

Honestly check the relay & the fuse b4 getting a new pump

[Brianmoooore]

No need for any guesswork! If you feed the fuel pump directly by feeding power to the outer fuse socket, and the fuel pump then performs faultlessly, then start replacing relays, but if you still get fuel feed problems with the temorary link, then it's the punp.