Question on Fuel Pump Testing

Hi Nick. R56 base that seems to get 10.9 volts to the fuel pump while cranking and jumps to 12 when starter stops before returning to zero. Fuel pressure reaches 50 psi over 30 seconds of cranking and drops to zero inside a minute. Engine never starts even upon reaching 50 psi. Could a faulty check valve or other leak still be causing a complete no-start condition even with proper pressure or is it likely I have other problems going on?

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This post was auto-generated based upon a question asked on our tech article page here: MINI Cooper R56 Fuel Pump Testing (2007-2011) | Pelican Parts DIY Maintenance Article

[Nick at Pelican Parts]

The pump will get battery volts, which is whatever battery voltage is at the time. 10.9 is your cranking battery voltage.

Sounds like a faulty pump or check valve. I would assume it would at the minimum try to start once pressure builds, unless volume is too low.

- Nick

[freelax]

Nick, I'm having fuel delivery issues and just tested my fuel pump on my 1983 911SC. I have replaced the pump within last year, but the multimeter shows about 8.96V across the terminals when motor is cranking. Battery shows 11.93-11.96V with no ignition switch activation... Is this be an indicator of not enough power to the pump?

[Luccia at Pelican Parts]

Originally Posted by freelax

Nick, I'm having fuel delivery issues and just tested my fuel pump on my 1983 911SC. I have replaced the pump within last year, but the multimeter shows about 8.96V across the terminals when motor is cranking. Battery shows 11.93-11.96V with no ignition switch activation... Is this be an indicator of not enough power to the pump?

Go to this tech article: Porsche 911 Fuel Pump Replacement | 911 (1965-89) - 930 Turbo (1975-89) | Pelican Parts DIY Maintenance Article and post this comment at the bottom. Casey may have some input for you.