There is a rattle when I hit the gas hard when accelerating, only in the front. Not the rear. Doesn't happen when back up, but I have back up hard bc that's dangerous hahaha but I think it might be the heat sheild around the engine. It's loud on the outside and inside of the car. It's very annoying and not sure where to start of finding where the metallic, vibration noise is coming from. I could use all the help I can get. This is my first car and want it to last a very long time. Car isnt new by the way. Has 137,861 miles

 

Check the engine mounts. While in park, open the hood and have a helper rev up the engine. Can you see the engine twist from the torq?

 

The engine will naturally twist a little when it's revved? What would I be looking for in order to see what's rattling...

 

If it's twisting excessively a motor mount is shot and the engine is knocking up against a heat shield. Look at the exhaust manifold if you see excessive twist. Also the honey comb in the catalytic converter could be broken internally.

 

Belt tensioner damper (shock). If you have a manual.