I have had a 2009 toyota camry for about 3 years now and when I was accelerating onto the interstate I heard a loud pop under the car and i think it came from the drivers footwell, that's when I could hear the engine in the cabin. My steering wheel vibrates with my engine. The noise is always there no matter what rpm or gear I am in. I removed the whole exhaust and started it up and still has the same issue. The engine is not any louder than it was before from outside the car.