Fuel pump will not prime

RuskiRacer

Captain
Jul 17, 2019
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2009 e93 335i
Installed dual 450s the other day went to start the car ran for 1 second and died logged on jb4 lpfp psi and it ready like 5 psi. Changed ekpm2 to a ekpm3 that I knew worked good on my last car with this setup. Checked fuse, swapped relay. Not sure what else to hit me with some suggestions. Pumps work because I hard wired it and my car ran for 5 seconds with the fuel pressure it built up.
 

RuskiRacer

Captain
Jul 17, 2019
1,209
757
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2009 e93 335i
I'm thinking my issue may be electrical. I have the float perfect this time the pumps and everything lined up better than ever before. I have mini jumper cables which I connected to the 2 prongs on the fuel hat and the pump forsure works and will build pressure to the rail and car would run for a couple seconds . My issue is I never even hear the pumps prime when I turn the car ignition on. I think its either my ekp not getting proper power or not delivering the power.
 

RuskiRacer

Captain
Jul 17, 2019
1,209
757
0
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2009 e93 335i
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NoGuru

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Jan 9, 2018
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Just North of Detroit
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BMW 335is
I see you have a Hobbs setup with the secondary pump connected to the battery but that should be irrelevant for the primary pump.
Double check the connections to it under the Top hat and make sure the plug is pushed all the way on on the top of the top hat.
 
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RuskiRacer

Captain
Jul 17, 2019
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2009 e93 335i
I don't believe they can be reversed ive done fuel pumps a few time no issues. I could put my old ekp back in but would not really see why to ? Maybe it could be wiring, is there more than 1 fuel pump fuse?
 

RuskiRacer

Captain
Jul 17, 2019
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757
0
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2009 e93 335i
I'm getting 12 volts to the fuel pump fuse ,12 volts to the relay and then nothing to the ekp connections . Would a bmp4 controller solve my issues?