I have a 2007 Grand prix with a 3.8 Supercharged engine. It was cold last week here in WISCONSIN.. but even at that it has been cold before and my car started right off. Lately it has been sitting there for awhile before it starts. I thought it was the battery and had it tested it only had 75 percent charge but even at that it did not seam to be bogging down to start it just rolled over a while before turning on. I then replaced the battery and same thing. Anyone know what else it could or would be? I called a dealership mechanic and he said it was probably something to do with fuel. I really do not want to pay a guy to tell me nothing is wrong. If my fuel pump is bad it is payed for under my 100 mile warranty. But if its not the fuel pump you gotta pay the diagnostic and then for them to figure out what is really wrong with it. LET ME KNOW.....now that it has warmed up it seams to be starting better but
