Friday, November 25th, 2011 AT 12:01 AM
99 Chevy k1500 5.7 4x4. Truck is running rough doesn't seem like it has all the power it should and is backfiring when I am driving slow and not giving it allot of throttle. I have already replaced the whole exhaust including o2 sensors from the manifold back. New maf sensor, new map sensor, new timing chain, new computer, and new plugs, wires rotor and cap only code I get is p0300. No mechanic can seem to fix it. Any help is appreciated.



