Passenger Side Buzzing Noise After Cat-Back Install

[NismoSlow]

So I just installed an aftermarket exhaust on my Nismo Z. Sounds great, and I'm really happy with it. However, I've noticed something odd.

When accelerating through the 2,000 to 3,000 RPM range, where the exhaust is at its loudest, I get a high-frequency buzzing noise that seems to be coming from the passenger side, somewhere around the dash vent/door area. It almost sounds like speaker distortion.

A few things I've noticed:

• Only happens in that specific RPM range.
• Goes away as soon as I'm above or below it.
• Goes away completely if I roll the passenger window down.
• Radio is always off, so it's definitely not the audio system.

My guess is that the exhaust frequency is causing some sort of trim resonance, but before I start taking panels apart, I figured I'd see if anyone else has experienced this.

Has anyone run into something similar after an exhaust install? If so, what ended up being the culprit?

 

[chadgigachad]

Which exhaust did you install? It could be hitting a brace in the rear.

 

[NismoSlow]

i installed the MBRP exhaust with everything else stock. It sounds like a high frequency ringing coming for the air vent on the passenger door.

 

[Leroy819]

I am completely stock and have this same noise coming from the right side of the vehicle but it sounds like it's the rear speaker next to the parcel shelf. It happens in that same RPM range and for the last two weeks I thought it was my fork/knife vibrating in my lunch kit on my passenger seat.

Did you find anything inside the car that was vibrating? I am wondering if my speaker has something loose inside of it. I notice it in the same RPM range and it must be an engine frequency thing. Over this weekend I will have a passenger and see if they can put pressure on different panels and make the noise go away.