I own a 2001 chevrolet silverado. My truck is throwing a p0171 and p0307 code I've recently changed all of the injectors, the fuel rail, air filter, spark plugs and wires. I've also checked for a vacuum leak and tested each and every coil pack to ensure they are working correctly (which they are). I changed the first O2 sensor on the driver side as well. My manifold has 2 broken bolts I'm just wondering if this could cause these codes and if not what else could.