2017 Mazda6 rattling/droning sound with acceleration

[MikaelaP707]

I’ve had my 2017 Mazda6 Touring for about 4 years and it frequently makes a low-pitch rattling noise on acceleration. Went to one Mazda dealership and they said the belt tensioner was leaking and replaced that and the drive belt, then they tried to say it was transmission noise after that didn’t help. Went to another Mazda dealership and they said it might be a bad wheel bearing noise, so they swapped my wheels for new ones, drove my car and said the noise was gone. I’m back in my old wheels now and the noise is still there.
It happens more with a colder engine and under medium to high acceleration.
Any guess as to what else this noise could be?

 

[imalwayssad]

Hey @MikaelaP707, rattling noise could just be a loose heat shield. It could also indicate exhaust issues, do you have the flex pipe still on it? That was a rattling issue for me, at some point, some random mechanic took my flex pipe off.