'95 Camaro Diagnosis

I have a '95 Chevy Camaro with a 3.4 liter V6. It's been sitting for about 3 years. It would turn over but would not start, so I replaced the fuel pump, fuel sending unit, gas tank, and filter. I sprayed gas in the breather and it started but it wouldn't stay running. Then I took the vacuum line off the fuel rail and it would idle and it would run, but as soon as I put the vacuum line back on it would die. Can anyone diagnose what could be the problem and let me know what I should change out (fuel pressure regulator?, injectors?, sensors?, etc...)?


Thanks,
Shane

sounds like fuel pressure regulator to me.

I've replaced regulator but wont stay running.