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A6 fuel pump not pumping

Old 10-06-2015, 05:40 PM
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Join Date: Oct 2015
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Default A6 fuel pump not pumping

I'm working on my Sons 2000 A6 4.2 Quattro. He took it apart 3 years ago for a timing belt change and did not finish it. Now I am putting it back together.

I don't know if any of this is important, but thought I better give a state of affairs in case I am missing something obvious.

He had put the wrong power steering fluid in. So he had me suck out what I could with the intentions of flushing the system. But that job is not finished. So Just to be able to start the car I left the accessory belt off so it would not turn the pump. So the covers and all that is left off.

Car will not start. We thought just because of old gas. Now I have determined it's due to lack of fuel. But it will start on starting fluid and seems to run fine.

I dropped the fuel filter and nothing is getting pumped by the fuel pump. The fuse is good and the relay clicks when I take it out and put 12v to it. But the pump that is under the rear seat is not powering up. BTW. Is there more than one pump on this car. I am getting 7.8v at the fuel pump harness when cranking it over. Is this voltage too low to energize the pump. Or is the pump bad. Again. Is there more than one pump in this car as I have read about on slightly different models.

I just thought of something. Is there some kind of sensor in the front of the car that will shut off the fuel pump in case of an accident. As I said earlier, the car is not put back together. The front bumper is off. I wonder if I have something unplugged that needs to be plugged in. Maybe that's why I'm only getting 7.8v to the pump. And assuming the pump need 12v to work. Or should it work on 7.8v and that is a normal reading.

I also want to show where I was getting the 7.8v. From the green/yellow and brown. Also 7.8v from purple and brown.

Attached Thumbnails A6 fuel pump not pumping-20151006_153050.jpg   A6 fuel pump not pumping-20151006_160737.jpg  
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