1995 850: Where is the fuel pump check valve?

[havegonetooz]

I am trying to figure out where the fuel pump check valve is. I have no pressure in the fuel line when the car is off, and it takes me a few tries cranking the engine to start the car.

I understand the check valve is in the fuel pump assembly.

Is the check valve in the metal pump itself, or is it in the white plastic case (housing) that goes around the actual pump?

[phils94850]

Its in the housing...

[cn90]

At this age and mileage, you are better off with a brand-new fuel pump.
Google Bosch 69693 and search for posts by "stephansvolvo" on how to install it.

Your other option is to install a separate in-line check valve.

[havegonetooz]

I've changed the pump insert with the Hella model (and pump relay) after the original pump failed. My understanding is the check valve keeps the line primed with pressure for the next start.

Could a new fuel pump have damaged the fuel pressure regulator to cause the residual line pressure to bleed off? Does the fuel pressure regulator even keep fuel pressure when the car is off?

[cn90]

There are a few ways to lose residual fuel pressure:
- Bad FP Regulator allowing fuel to return to the gas tank when it should not
- Leaking Fuel Injectors
- Leaking Fuel Lines
- Bad check valve

You need to work your way through these issues...

[havegonetooz]

Ok, thanks for the info...

[Ozark Lee]

A bad fuel pressure regulator will often rupture the diaphragm which allows raw fuel to leak / get sucked directly into the intake manifold. You would know that though since the car would run incredibly rich and have black smoke.

...Lee

[phils94850]

On a 94 turbo I had the hose coming from the fuel pump to the line in the fuel pump assy. had come loose which was causing my hard start problem.