2008 Chevy cobalt LT coupe has troubles starting sometimes, will start right up sometimes, but other times i crank it so many times and no start.

Sometimes, you can cycle the key on and off several times before you crank it, to see if it helps? If it does start quicker, then, I would check the fuel system. Use a gage to check fuel pressure, key on engine off, my info says 50--60 psi. You might also check proper voltage and ground at fuel pump when problem is ongoing. The basics, if it cranks good but won't start, make sure the battery has a full charge. Have helper crank it while you check for spark at the plugs. If spark everywhere, use a gage and check proper fuel pressure also check fuel injector pulse. If a problem with more than 1 system, we may have to rethink diagnostics. Just my opinion.