I have a 07 Cobalt SS SC and i am having serious engine problem.... I took it to my dealership and they told me that when i changed my stock spark plugs with the bosch 4 points that it might have damaged a cylinder... Plus they said they cant get one of the spark plugs out.... They said that i need a whole new engine.... Is this a problem that could be solved by simply just removing the spark plug and or maybe just replacing the head... I also got a offer on a new engine for 6000 from the dealership..... I just need some feed back.