The rhythmic hum of Camry cabin! Even when idling! Today, after cleaning the fuel injector and throttle, the noise is even louder! What's the problem? thank you

According to your description, you can't hear it after opening the hatch cover, but you can hear it in the cab, which is a rhythmic hum; 1 No problem if the engine does not shake. It is recommended to check whether the exhaust pipe leaks; 3 Check whether the muffler is out of welding (whether the internal sound insulation layer is out of welding) and leaks; 4 Whether the exhaust muffler is hung reliably. I hope it helps you.