Welcome to 2CarPros.
That's a tough one. When reading your post, the first thing I thought was an exhaust leak. However, I would think you would hear it when you hit the gas in park too. Just for the heck of it, check around the exhaust manifold and all connections under the vehicle. Also, has there been any notable power loss or change in fuel economy that could indicate a partially plugged converter?
Let me know. When checking, check where the oxygen sensors screw into the exhaust. Also, if it is loud enough to record, can you record it and upload it for me to hear?
Saturday, June 15th, 2019 AT 6:21 PM