Hello. I have gone through the typical crank/no start fuel rigamarole. The occasional stall which would start right back up became more frequent and eventually left me stranded. I've replaced the fuel pump, fuel filter, fuel rail pressure sensor, the PEM and I've cleaned and tested the variable timing valves. After all that, I have 0psi at the rail.
I opened the tank and turned the key. The secondary/scavenge pump immediately brings fuel over for a few seconds and then shuts off. The primary pump pushes no fuel (I connected a clear tube and ran it out of the car so I could watch). I removed the pump, filled the reservoir with fuel and then connected straight battery power to the main pump and it moved a lot of fuel. Because the main pump doesn't even pressurize when the key is turned on, I know it's not a kinked line or hose problem. I'm starting to think that the pump I bought is wired incorrectly and that it is running the wrong pump initially. The car has 325,000 miles on it and is in great shape. I don't want to give up on it. Any suggestions would be greatly appreciated. Thank you.
No Fuel Pressure - 2005 XC-70
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ADiFrischia
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- Year and Model: 2005 XC70
- Location: Pennsylvania
- jonesg
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You removed the new pump and fed 12v to it, but you didn't check if it was getting 12v at the pump harness.
If it was getting 12v before you replaced the pump, sounds like it just wore out .
and its getting power to the low pressure pump, ...
I'd check at the plug by back probing to see if there 12v present for the main pump.
The two pumps have independent feeds controlled by the ECM or PEM or whatever.
anyway, watch this, he describes it better and shows which wires you can test probe.
If it was getting 12v before you replaced the pump, sounds like it just wore out .
and its getting power to the low pressure pump, ...
I'd check at the plug by back probing to see if there 12v present for the main pump.
The two pumps have independent feeds controlled by the ECM or PEM or whatever.
anyway, watch this, he describes it better and shows which wires you can test probe.
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vtl
- Posts: 4734
- Joined: 16 August 2012
- Year and Model: 2005 XC70
- Location: Boston
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You probably got a pump for non-PEM car. It runs at constant 12 Volts and relief the excess of the pressure via ball valve, while PEM-equipped car modulates the pump the with PWM signal (pulse width modulation), typically at approx 35% duty cycle. Any info on part number you've got?
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