Off topic sorry to steal you post, But could a header leak cause overheating???

 

well i have another problem now.... i found that spark plug like and took it out and put i back in straight, well my car cranked up but was running very ruff, so i got another spark plug and put the new one in and now the car will not crank at all and just sputtereds and tries to start....this is driving me insane

 

it will start but i have to give it gas to keep it running and its idles and runs VERY ruff!!! there is some old spark plug wires on there, do u think it could be making it run ruff like that? would 2 cylinders or 1 cylinder misfire make it idle really ruff?