Q: I installed a boss 302 manifold on my 13 mustang gt 5.0 and the bolt in the middle pasenger side craked but the other bolts are in.

Hi there. The bolt that cracked the manifold will not cause the cylinder 1 to misfire. The misfire is caused by a faulty spark plug, a faulty spark plug wire, a faulty fuel injector, or a burned valve. Check the spark plug and the injector on cylinder number 1. If they are working properly, then check the compression on the cylinder and compare it to the other cylinders. If cylinder number 1 has a low compression, then hook up a leak down tester (requires compressed air) and see where the leak is coming from. If you need further assistance with diagnosing a misfire, then seek out a professional, such as one from Your Mechanic, to help you.