Loud Rattle When Starting Up

[Stolzies]

I have an 06 M35X that just turned 100K miles. I am recently noticing a noise that sounds like a rattle (kinda tinny) that is most noticeable when first starting the engine and at low idle. It has gotten progressively louder and more noticeable over the last couple of weeks. It becomes louder when pressing lightly on the accelerator. My first impression/guess was that is coming from underneath the engine and possibly the exhaust (not the rear) or catalytic converter. Is this a possibility? Any other ideas? I do plan to take it in to the dealer but wanted to get a jumpstart on this.

THANKS

[Stolzies]

One more detail about the noise...in reading other forums/posts someone had a similar problem and described the noise as rocks in a tin can. I believe that is an accurate description of my noise.

[TXT]

This is a video I made of my car. Sounds similar to the issue that you are having.

https://www.youtube.com/watch?v=W6IhwLyuyHE

I got my oil changed a couple of days after and it fixed the issue.

Right before my next oil change was due, sound came back. Got my oil change and sound went away.

Im sure it has to do with low level of oil. Car loses a bit of oil and eventually gets lower than it should so im guessing it causes this noise....my guess.

[TXT]

Heres another

https://www.youtube.com/watch?v=rSfUzWM81Tg

[infiniti007]

I have the same sound happening to my car... I have an 03 m45 with 95,000 miles... I am thinking it might be the idler pully or belt tensioner .. going to take to a mechani to find out

[Stolzies]

All-thanks for the replies. Definitely not a pulley as the noise comes from underneath the car not in the engine compartment. Also oil level is fine. I did some additional research and I am fairly certain it is either a CAT or the heat shield. More likely the heat shield as it seems to get better as car warms up which would indicate that the metal expands and the vibration is not as severe. I am bringing it to Dealer on Monday.

[candymanfb]

My issue was solved with a $20 weld to the exhaust system. My independent mechanic showed me the problem during an oil change. The problem was near the CAT - a leak.

[The00Dustin]

I was going to suggest exhaust because I remember several people having problems with their Y pipes (I think, maybe it was X pipes). Infiniti was saying it was microfractures and not covering the repair under warranty. It seems like one person found that it was the heat shield and not the X or Y pipe itself. Regardless, anyone searching that finds this thread might want to try searching for those threads (I didn't, my searching skills are weak).