Q: Car makes a metal rattling sound when stepping on the gas. It has gotten worse over time?

asked by on November 29, 2016

A few weeks ago, I noticed a slight rattling/ticking sound coming from the engine when I stepped on the gas. I would let off of the gas and it would immediately stop. Then I would step on the gas again and the car would accelerate normally with no unusual sound. However, I always seem to notice a burning smell around the same time all of this happens. Over time, the noise has gotten louder and more constant. Now I hear it when I first step on the gas and continue to hear it while my foot is on the gas. When I take my foot off of the gas, the sound slows and stops but the sound is heard every time I step on the gas now. The first few times I step on the gas while driving, I still get that burning smell that accompanies the sound. I scanned my car to see if it was kicking any codes and got nothing. On October 19th, I got my brake pads, rotors, the front left caliper, and the drive belt & drive belt tensioner replaced. Any Ideas as to what is causing the rattling? Thanks!

My car has 164000 miles.
My car has an automatic transmission.

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Hi there:

There could be multiple issues causing the rattling noise when you accelerate on your Mazda 6 ranging from a loose bracket, to an exhaust pipe that is cracked or even the serpentine or drive belt system that’s causing these symptoms. It’s also possible that motor mounts are starting to show signs of wear. The only way to really know for sure what’s causing this issue is to have a local mobile mechanic complete a car is making a noise inspection.

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