65lbs fuel pressure but only for 2 seconds

Hello, first off, great site!

1995 Chevy Astro AWD 195,000

My issue is, I'm not getting any fuel pressure at the fuel pressure check valve. When I turn the key, I get 65lbs of pressure during prime, then it falls down to 15lbs and stays there.

I got the upper intake manifold off; no leaking fuel regulator and no leaking plastic fuel lines.

I now have the fuel pump and sending unit out but I don't physically see anything wrong with it. Pump and sending unit is less that 1 and a half years old. I bought OEM pump and sending unit.

I attempted to cap both the plastic lines leading into the injector with a rubber hose and clamps at each end. I then attempted another pressure test however, I got the same results: 65lbs during prime, 15 lbs thereafter.

This leads me to believe the pump is leaking somewhere inside the tank...

Also, no fuel line leaks.


Any thoughts?

Thanks!
Brad

So what was your original problem? rough idle, running rich? what made you decide to test fuel pressure.....

Hello,

Cutting out while driving, non start conditions.

If the OEM brand pump is not in the tank- then put it in....I don't favor aftermarket pumps....

If you have the fuel pump module out, there's an easy way to test the check valve and flex line. The 3/8" fitting on the pump module is the pressure line. Slide a piece of 3/8" hose onto the module fitting: you should be able to suck on the hose with very little resistance, and you should NOT be able to blow into it, at all! If it fails this little test, replace the module. I check every new pump I install, before I install it.