hello fellow sl members. i have a buzzing noise in my engine bay that i cannot figure out. i have already put rubber on my intake so it's not the intake rubbing the fender. the sound is only present while shifting and in low-mid rpms. i can't figure out what the buzzing is from. my brother says it sounds like it's coming from the passenger side. i have no clue what it is and it's been happening for a looooong time!! my car sounds like crap!! someone PLEASE help!!

**UPDATE**
here are a few quick videos that my brother took so you can hear the buzzing i am talking about. (sorry for the quality, and amateur video skills) i am driving weird so i could make the buzzing occur as much as possible.

http://www.youtube.com/watch?v=VcmjaVerKjw

http://www.youtube.com/watch?v=A5RRyK2tHXQ

 

Not too sure, but isn't that a grounding issue with the alternator?

Doesn't the Big Three upgrade eliminate that?

 

It's had to say what it could be. Usually the motor vibrates a little in lower gears with more fuel but, if it is a bad buzzing. You might want to try and find out what area of the motor its coming from.

 

Drive without your bumper on and see if it still happens. If it doesn't, then you know it's under the hood. Does it only buzz at the same frequency or does it get faster as the RPM's raise?

 

With all due respect, I have no clue what you're talking about. Lmao!! Elaborate please.

 

I know that the motor vibrates when accelerating which is normal (as long as it's not accessive). And I'm pretty sure the sound is coming from the passanger side. I checked my header and it's secure so I'm sure that's ruled out...I'm so lost and it's really embarrassing that I have a nice sounding exhaust setup but my car sounds like crap from that sound...

 

That's a good idea, I'll probably try doing that. The buzzing is at the same frequency even while rpms raise. Although, it doesn't happen for the first minute or so...it's like it only happens when the engine is warm. Thanks to everyone who is trying to help, I'm very appreciative. Please don't give up on me!! Lol...

 

Keep us updated.

 

So, my friend and I jacked up my car and we went through a pretty crazy test to try figuring out what's going on. We have come to a few possibilities which include my header, s-pipe or the donut gasket that is between the two. The sound does not happen at idle, only occurs when the engine is warm, and only up to 3000rpms. We even jacked the car up an put it in gear to see if we could hear it, nope!! The car must be on the ground to be making the noise. We are going to put the stock header back on Friday to see if we can further narrow the source. Again, thanks to all who are helping me out and please don't give up on me and my tC!!

 

hey killer, yeah I think it's in the exhaust too, but just check out the drivebelt side of the car and make sure the noise isn't coming from the belt tensioner or the water pump, that can make a sort of metallic rattle like you're hearing.

but if you don't find anything there, then yeah check the exhaust might be a heat shield.

 

So, I finally had a chance to jack up my car yesterday and figure out what this annoying noise was. Turns out it was the donut gasket that goes on the header!! When my friend and I put on the DC header we forgot to put on the friggin' gasket!! The test drive following the installation of the gasket was mind blowing to me. My throttle response is waaaay better, I can feel more torque, and of course the buzzing sound is gone. I'm pretty sure I will notice increased gas mileage as well. I am ridiculously happy that I figured out the problem and fixed it. If it weren't for you guys leading me in the right direction, I would still be here scratching my head...lol. Thanks guys!!