97 Chevy Astro fuel pressure drops when fuel pump stops

I have a 1997 Chevy Astro Van 2WD 4.3L with 111K miles. It was starting hard (2-3 long cranks to get it to start). I suspected the fuel pump (that was the problem the last two times it acted like this). I checked the pressure and, when you turned the key, it would slowly make it to the 55-60 psi range. However, it wouldn't not stay there. It would drop down to 0 once the pump stopped running. I figured that was a problem with the pump so I replaced it (it was still under warranty so that was the cheapest solution). With the new pump, when you turn the key it shots right up to 60 psi put still won't hold that pressure. It starts a little easier (usually by the second crank) and the pressure is pretty steady when the van is running. I thought that, after the pump shut off, the pressure should stay up for a period of time. Is that correct? If so, what, besides the pump could be causing this problem? The fuel injector pressure regulator possibly? Anything else? Is there a way to check for sure if the regulator is causing the problem?

Thanks for you help

ngpost1

yes the pressure should stay up for 15 minutes or longer, you have a problem with the pressure regulator or check valve, the check valve is in the tank in the sending unit or pump, if the regulator is leaking witch is not likely by what you described it is in the injector area

Absolutely no problems on warm restart aside from taking 2tries to start it; which it does when cold also. Is it safe to assume since I replaced the pump (which includes the sending unit I believe) that the problem is not the check value as previously mentioned?

or..... you have a leaking cpi unit (very common). You will have troble on warn restart, will act as if flooded (because it is).

My wife's 97 chevy astro mini-van has over 150miles and it was having a similar problem. It turn out to be that some of the injectors on the CSFI were leaking. Which would seem to cause the engine to flood when sitting over night, but when warm it would not have any starting issues. Had to replace the entire fuel injection unit with an after mark one that was cheaper and its been working great for over 2years. Good luck.

A.P.

A.P. welcome to the forum, and thank you very much for that input