cruzmisl

I don't think the TSB/muffler replacement is worth it. It will sound the same on start up.

I had 3 mufflers replaced under warranty because the REPLACEMENTS had problems where water would build up but would not evaporate. I ended up having to buy an Sport Exhaust (800 option from dealer) off ebay to make my car sound decent again, because the dealer found nothing wrong with the replacements.

DONTTASEMEBRO

what type of sport exhaust from the dealer?

ypdfwg37

I think it leaks somewhere, or something loose. Lift the car up and recheck. Is your exhault OEM?

M3ng

I have the same issue. I recently bought a used 2008 g37s coupe and mine sounds loud at first....I mainly hear the rattle when I turn off the car(just before the engine shuts off and the car shakes a little---with the driver side door open)I read about the tbs on a google search and found that its common for the 08. Let me know if you enquire from the dealership if they would service it for free after warranty, I'd like to know.

guy from norcal

iTrader: (2)

sounds like my sedan too. I believe thats the catalytic converters just warming up.

socketz67

It may be the cats. I never thought of that. It's amazing how much different the exhaust looks on my 13' compared to my previous 04', so I am reluctant to compare the two. On the 04' it looks like they went out of their way to tame the exhaust, and on the 13' there appears to be little that can be improved. Down to the equal length exhaust manifolds, which in my understanding are equivalent to headers. My guess is that some of the racket we are complaining about is related to the nature of the less conservative design on the newer models.

Finzel

I know this is kind of an old thread buy my new to me 2011 G37x is very lound when it first starts up then quiets down rather quickly.
If your like me, to hear that "its normal, they all do it" just is not good enough. That is exactly what the dealer near me told when I called and asked to speak with a service advisor, not that they would have a clue.
I found this answer on the 370z Board, being some what mechanically inclined it makes perfect sense to me. Hope it helps any one out that might pop in for the same reasons I did to this thread.

Enjoy!!

Cold starts : engine / exhaust sound - Page 2 - Nissan 370Z Forum

ai3j50

My boy that straight piped his M3 had cold start disabled during a tune. Did it as a courtesy to his neighbors. G37 can probably be tuned in the same way if it really bothers you that much.

Ryne

iTrader: (12)

Finally emmission controls doing something that benefits the enthusiast. I like the loud cold start! Look forward to it every morning.

infinitiman96

@Finzel you are correct, its completely abnormal which is why I started this thread in the first place. There is an updated muffler which corrects the rattling can noise on cold start. The 2008's apparently are prone to this issue which is why Infiniti has a TSB for this. Unfortunately I don't see the value in spending $700 to replace the muffler so I've just learned to live with it.