Okay im a swedish rookie. 2005 s40 t5. Fuel pressure guage shows good running fuel pressure .60 psi at start for 10 sec then settles to 45pi running pressure. After engine off fuel pressure drops to 10-15 psi. I think i need a fuel pump due to a failed check valve. Is the check valve in the fuel pump for sure. Also i have heard about fuel pressuer regulator problems on these vehicles. Any words? How bout link to good priced parts?

 

Regulators? wrong year I believe, 2004.5 and up is a newer S40.

I have not seen many fuel pumps in these cars, but it sounds like it. I am not used to using PSI on a gauge with these cars, Kpa is what we use, but this sounds too low, it should have a decent pressure for 20 minutes at least.