The fuel pump on my 3.4 2004 monte carlo ls no longer primes when the key is in the on position.The fuel pump relay still clicks. No issues when the car is running . Just a few hard starts when the car is sitting for a while.

 

check fuel pressure. could be a bad regulator or leaking one way valve in the fuel pump assembly. hard starts likely indicate a leaking check valve in the fuel pump, if that is the case your fuel pressure will drop after the key on ignition off initial fuel pump prime

 

It wound up being the fuel pump. Didn't think it was the regulator since I replaced it last year. Thanks for the reply.