Accel/Decel "Rumble"

[flintoh]

Hello all, new to the thread. I just purchased a used 2020 ST 2 weeks ago and have started noticing a fairly harsh rumble when I accelerate (normally) from a stop, or even a rolling start. Seems to be around a certain RPM, maybe 1300-1500 if i had to guess. The rumble also occurs on deceleration, at the same RPM. I read a lot about the flex pipes, but im not sure if that is the cause. The entire pipe on the driver side is rumbling upon startup, and I can tell by the sound that it is the same rattle that I am experiencing while driving. What could the diagnosis be?

 

[Cdubya]

could be the flex section has a leak. Could be tha catalytic converter downpipes have a leak. could be a leak in another part of the exhaust. All 3 are fairly common for a MY2020

 

[BrooseDaMoose]

Welcome to the forum! Good to see another Mass resident ST owner here. As stated above, it could be you have a cracked/broken weld at the converter in the down pipe. Very common issue.

 

[flintoh]

Thank you for the replies. Going into the shop on the 21st for the techs to have a look, will keep this post updated.

 

[2020FordRaptor]

Hello all, new to the thread. I just purchased a used 2020 ST 2 weeks ago and have started noticing a fairly harsh rumble when I accelerate (normally) from a stop, or even a rolling start. Seems to be around a certain RPM, maybe 1300-1500 if i had to guess. The rumble also occurs on deceleration, at the same RPM. I read a lot about the flex pipes, but im not sure if that is the cause. The entire pipe on the driver side is rumbling upon startup, and I can tell by the sound that it is the same rattle that I am experiencing while driving. What could the diagnosis be?

Sounds definitely like the flex pipes.

 

[flhx06]

I would say flex pipes too. I am having the same issue at 1100 - 1300 rpms. Put my car up on a lift and set the RPM's at 1200 and ran a video and then a video at idle. You can definitely see the vibration at the flex pipe on the drivers side. I've also had the the pipe break at the converter. I have finally decided to go to an aftermarket exhaust and will be ordering the AWE setup shortly.