Pontiac Repair: Pontiac G6 starting., 2006 pontiac g6, pontiac g6

Question
I have a 2006 Pontiac G6 with a V6, 3.5 Liter engine.  Good car, sometimes when we go to start it, it stutters, and sometimes will start and sometimes not.  It will kind of shutter.  We have to wait a few minutes and then try again, usually stepping on the gas pedal to get it to start.

We had a new battery put in last summer, new spark plugs, spark plug wires and such.  New gas cap.  No engine lights come on when this happens.  And none when we're driving.

Just wondering what's causing this.  We keep the oil changed and everything.  We noticed there are instructions on what to do if this happens in the manual.

Just want to make sure we're doing everything right.  Thanks.

Answer
Hey Jae:

3 things I would look at for this. #1 make sure the throttle plate is clean a carboned up plate will do all kinds of wierd things for starting and idle concerns. Fuel pressure need to hold steady at key off if the pressure drops off either from a leaking injector or a pressure regulator in the pump or a bad check valve in the pump the fuel in the fuel rail will vapor lock and cause issues. lastly That engine had multiple updates for the engine control module for engine running concerns Not sure what they were all for due to it bing so old I rarely see any of them anymore due to them all being out of warranty. Also there were issues with the UBEC (under hood buss electrical center) "fuse" box with bad connetions cauing issues as well. Good luck :-}