Fuel pump check valve?

[bwh13]

My 320,000 mile 1988 325is fuel pump doesn't seem to hold pressure after I shut off the engine. Is there a way to check the valve that is supposed to keep the pressure in the system?

[bcrdukes]

I would just get a new one. I bought one not long ago from Pelican Parts for something like $7 give or take a few bucks?

[jlevie]

While it is possible that only the check valve has failed and the pump is otherwise in good condition, a pump in good condition will achieve normal rail pressure starting from zero pressure in a turn or two of the engine. If that's not happening, you need to replace the pump (which will include a new check valve).

There can be other causes of hard starting after the car is parked for a while. Before concluding that the cause is a loss of pressure in the rail you should run the fuel system test suite. Then you'll know if the fuel system is at fault and what might need replacement.