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Marty
Marty, ASE Certified Technician
Category: Mercedes
Satisfied Customers: 53166
Experience:  Bosch Certified Master Technician with over 35 years experience in the automotive industry.
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Just slowly cut out one the petrol pumps was making ahumming

Customer Question

just slowly cut out one the petrol pumps was making ahumming noise but when car had stopped no noise even with the ignition turned on everthing else working but no fuel being pumped up checked connections on pumps with voltage meter was only 1.7 not enough power to pump fuel can any one help please
Submitted: 1 month ago.
Category: Mercedes
Expert:  Marty replied 1 month ago.

Hi, there is only one fuel pump on your Mercedes. You should be measuring from the brown wire to the red/green wire with your voltmeter while cranking the motor. If you have 12V when cranking and you have no fuel pressure you simply need to replace the fuel pump. If you are not getting 12V to the pump I would check the fuel pump relay.

Let me know if you have any questions.

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