Is it normal for an exhaust to change tone overnight? I got in my car this morning and my injen sounds completely different. My brother says it could have been because my friend was washing his truck and shot water up my exhaust. Is this true?

 

yep.

it does change but not bc of water

 

this is normal. i hear it gets louder for the injen.

 

yea with the injen xhaust the glass pack in the muffler disinigrates and come out, happened to my friends 350z.