1996 Old Cutlass Supreme 3.1 starting issue?

[Moose]

My 96 Olds starts great in the morning and if I shut it off and start it within 5 min it starts great but if I leave it sit 30 min I have to step on the accelerator to get the car to start. I've done a little research and I am leaning toward replacing the temp sensor any other suggestions? I have already cleaned the MAF sensor with MAF sensor cleaner.

Thank you for the help.

[Jeremy airjer W]

Check the fuel pressure regulator to see if its leaking fuel through the vacuum hose.

[Moose]

airjer I checked the vac line going to the top of the sensor connected to the front fuel rail and it seems to be good there and where it connects to the electronic box on the back of the motor. The line that goes from in front of the throdel body to the back of the intake manifold seems to have a bad o ring on it could this be the problem?

[Jeremy airjer W]

There was no fuel coming out of the fuel pressure regulator with the vacuum hose removed?

I think the next step would be to check fuel pressure. Shoud be 41-47 psi and should hold that pressure ith the key off. If ful pressure drops and the regulator is not leaking than the fuel pump check valve is bad.