Install aftermarket fuel check valve

rootleaf · Post by **rootleaf** » 23 Feb 2020, 08:28

Have an 07 S60 2.5t. The fuel rail looses all pressure after sitting overnight which produces long crank time hard start. The fuel pump and relay are good car runs beautiful just losing the fuel pressure over the course of several hours down to 0 pressure. I do not smell fuel loss anywhere so will assume from what I read on the forums its the check valve which is built into the fuel pump. I can survive by just turning the key to position 2 for a few seconds which builds the pressure up and then I get an immediate start which I have been doing in the meantime. But I am toying with installing an aftermarket check valve somewhere since I dont want to take on the task of replacing the pump over something as trivial as the check valve that is not affecting drivability. So, I do see some people have done this on previous year model cars but I dont see anyone trying it on s60 2001-2009. Can anyone tell me if it has been done, where the best place to install is and is there a particular check valve requirement or any aftermarket check valve will do? I would like to find a spot under the hood to install it for ease of access. Interesting enough, we have had 5 volvos with this same engine and two of them with over 250k miles yet this is the first one to develop this problem with only 112k miles.

Post by **oragex** » 23 Feb 2020, 10:40

Do you have a fuel pressure sensor at the rail ? I would look into that one first.

Post by **abscate** » 23 Feb 2020, 11:26

Spec on P2 is something like 52 PSI while running, and 30 psi after 20 minutes

There is no spec for overnight, so I would not put any hardware in until you check against spec.

Post by **RickHaleParker** » 23 Feb 2020, 12:36

rootleaf wrote: ↑23 Feb 2020, 08:28 Can anyone tell me if it has been done, where the best place to install is and is there a particular check valve requirement or any aftermarket check valve will do? I would like to find a spot under the hood to install it for ease of access.

I would install it as close to the fuel pump as practical. To prevent the fuel line between the aftermarket check valve and the pump from draining.