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Hi, sorry for the wait it looks like Michael is not online. My name is***** you describe in detail the problem that you are having?
Hi, it could be a bad pump or relay. You will need to test the voltage to the pump when it doesn't turn on. If you have battery voltage to the fuel pump when cranking the motor and there is no fuel pressure you will need to replace the fuel pump. If you have no battery voltage I would replace the relay. I've also seen the rear SAM cause the problem of no fuel pump operation on the C class. The SAM is the rear fuse and relay box in the trunk.
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