I have a 2014 GMC Sierra slt truck with a 5.3 engine. It has 11400,00 miles. Sometimes it has a rough idle, one day it will run smooth and the next day it runs rough. I had one week that it ran perfectly smooth and the next week was rough. I have replaced the spark plugs, wires, coils, injector’s, throttle body, excelerator pedal, and other sensors related to the engine. And all parts are GM parts. Someone said I might need to have the computer reflashed. Do you have any thoughts?
Well lots of reasons can make it do that from intake, manifold gasket, leaks, head gasket, leaks, worn valves, etc. But you said you changed the injectors. You might have a guy like me check the injection system out. The injectors may need to be balanced with a high-level computer. That mechanics like myself have. Pray it's something that easy and not a worn out engine
