Enter your question. My 04 silverado 5.3 is missing and has no power unless I floor it ive replaced o2 sensors and maf sensor plugs wires clean the screeen in the fuel pump still cant get it runnig better
Is there a check engine light? A couple of guesses are checking fuel pressure physically, and determining it is adequate, 55-60 psi. Another possibility is a restricted catalytic converter on either one bank or the other. If/when you determine fuel pressure is adequate, a way you can determine a plugged exhaust is to remove the precat sensors from one side or the other. Run the vehicle with the oxygen sensors removed, and if power is restored and no longer misfiring, you need to replace the catalytic converter.