Fuel pump not working

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E30foz
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Wed Nov 17, 2010 9:32 pm

Right i've got a prefacelift Alpina C27. Car has been on carbs but returning to standard so fitted manifold and new wiring loom as old 1 was butchered. Problem i'm now having is that the fuel pump won't kick in from the ignition. If you bridge the relay it will start but as mentioned won't work from the key. Now i've checked all the earths and checked continuity of all the wires running to the fuel pump and main relays. So now basically i'm stuck. Can anyone point me in a direction of where to start looking.
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daimlerman
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Wed Nov 17, 2010 10:19 pm

ECU switches the fuel pump when it sees the crank turning.

So I would start to look at the CPS and it's wiring.
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Brianmoooore
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Wed Nov 17, 2010 11:56 pm

As daimlerman says, the fuel pump shouldn't "kick in with the ignition" - only when the crankshaft starts turning. Does it? If so, you are looking for a non existent fault.
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E30foz
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Thu Nov 18, 2010 12:09 pm

It should turn on for a couple of seconds to prime the system shouldn't it?
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Brianmoooore
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Thu Nov 18, 2010 2:26 pm

E30foz wrote:It should turn on for a couple of seconds to prime the system shouldn't it?
Some older versions might, but this is largely a myth. A fuel system in good order is capable of maintaining the pressure for several days.
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Donnystreeterroist
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Thu Nov 18, 2010 8:19 pm

havin a similar problem with my pre facelift 320, the fuel pump used to kick in when the ignition was switched on but now it doesnt, where is the relay located and does anybody have a wiring diagram for the fuel pump/engine ecu??
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