AWD fuel delivery problem

johhny5 · Post by **johhny5** » 27 Oct 2008, 13:31

I recently replaced both left and right pumps on a 2000 xc70 due to a no fuel problem. About 2 weeks later, the car came back and for a no start problem. It showed about 6 gallons of gas. When I added gas, it would start. I assumed one of the senders was installed incorrectly. After extensive testing, I found that the problem is that fuel from the left side is not being delivered to the right side. I thought that the right side pump sucked fuel from the left side, but it appears that it requires pressure from the outside line of the left pump to push the fuel to the right side. The line that comes off the left pump goes to a pressure valve which T's into the evap line, which runs from the evap valve (on the fan) to the carbon canister. That is where I am lost, because as far as I understand the evap system on this car uses vacuum. Any thoughts or ideas would be appreciated, thanks.

johhny5 · Post by **johhny5** » 30 Oct 2008, 15:09

After further digging, I found that the pressure port coming off the line is actually a pressure regulator that ties in with the fuel line (very hard to tell). Anyways, I'm not getting flow out of the regulator, so it should be fixed when replaced. I advise anybody who does a fuel pump on a AWD with this set-up to check and make sure you have fuel coming out of the left line on the left pump.