Hello, I have a 2013 infiniti G37s Coupe, when the car accelerates from low speed after a speed bump for example or from a stop, it produces this rattling noise , it only happens during light acceleration at around between 1000 and 2000rpm.

Some info :
1. I bought the car used about 4 months ago and it's always been like this.
2. the noise can't be reproduced while idling, only when the car is lightly accelerating from a stop or low speed.
3. i replaced: sparkplugs, driveshaft, transmission mount, catalytic converters, checked all bushings they weren't in the best shape but not horrible.
4. i have already checked the entirety of my exhaust system (cats, hangers, muffler, heat shields) everything is fine, also i replaced the cats and removed all heat shielding as it was rusty and bad.

i've been trying to figure out this issue for so long now.
I've attached an audio file with the sound, it happens right before i use my blinker, couldn't figure out how to attach a video with my post iam new here, any help would be greatly appreciated 🙏🏼.

 

I can't open the file on my work computer. I suspect it's a piece of the catalyst inside one of the catalytic converters bouncing around inside. Once they warm up, the piece that broke off sticks to the main catalyst material and the rattle goes away. This is pretty common.

If you live in a state that allows aftermarket or no cats, you are in luck.

If you don't, then you will need a new Cat.

 

hello thanks for your reply, i forgot to mention a few details in my post, i have already checked the entirety of my exhaust system (cats, hangers, muffler, heat shields) everything is fine, also i replaced the cats and removed all heat shielding as it was rusty and bad.

 

Just a shot in the dark…I had an s13 way back in the day and the timing chain used to slap against the top guide. How do I know this you might ask? After a night of my car shutting off multiple times, it finally didn’t start again and the next morning I took the valve cover off and the intake cam gear was facing towards the sky, no chain guide or chain (chain fell lol)

I’m not saying I’m 100% certain it’s your timing chain but it is a Nissan lol but I will say that sounds different, almost valve train noise. Have someone sit in the car and rev the car to when it makes the noise and hold it there, take a long screw driver and try pin pointing the noise. Have you checked oil level/did an oil change? Do you hear AND feel the noise/vibration or do you just hear it?

 

hi thanks for your reply, like i mentioned in my post the noise does not happen when revving the car in idle, only under light acceleration from low speed or a stop.

regarding oil levels they're mostly the same since i did an oil change around 2 months / 500 miles ago.

i can hear and feel the noise aswell.

 

Just curious is your car an automatic or manual? You could put your car on 4 Jack stands that way you can put the car under load and you or someone sit in the car and try and replicate the issue. Could be mounts going, if your car is a manual and you haven’t replaced the clutch yet the OEM flywheel is a dual mass flywheel and they will vibrate when they start to wear out. Mine did, I replaced the clutch and replaced the flywheel with a single mass and no more vibrations