fuel pressure

I have a 2007 TrailBlazer LT 5.3 V8 with the following problem: When I measure the pressure with the key ON, the fuel pressure is at 50psi, ignites with difficulty and once it ignites the fuel pressure goes to 95psi immediately and when the key go back to ON the pressure drops to 0. No idea...

So while repairing a coolant issue I found that my vacuum line from my resonator to my fuel pressure regulator was broken. It broke right where the line enters into the rubber elbow. I have read that having this little line broken will cause your vehicle to idle rough or not properly. I have...