My car is making a weird noise! HELP!

lkh5650

Hello guys, I am not sure if I post this here or on the other section. Sorry if I am posting in the wrong section.

My car is 2010 370z sports package manual (not touring or nismo).

I was driving home and I was for some reason not paying attention to my speed and I suddenly I noticed that I was going at 90mph and as I was about to step on a break i started hearing loud noise as if something is stuck between the wheel and inside the car (normally I go maximum 80 mph). It was so loud that I was worried something happened to my car and I was about to pull over and call a tow truck or something. But as I slowed down below 55 mph, the noise went away. So I decided to drive back home and during the ride, i noticed a few things.

The noise won't come up as long as I go below 62~3 mph
The noise comes out when I go above that and goes away when I slow down to ~55mph.

after I got home I checked between all 4 wheels and the bottom of the car, noting looked out of ordinarily visually.

What is wrong with my car? I am planning to take it to a dealership or a service center..

PS: last time i drove faster than 80mph was probably about a year ago. I got oil change recently @41000 miles (replaced filter too). I am around 41500~42000. All of the driving was done on 6th gear, I didn't test if my car would make the same noise on 5th gear at above that speed.

thank you so much for your help.. I am panicking T_T

jaedub

What kind of noise is your car producing? Metal to metal screeching sound? Plastic to plastic? Is it a knocking sound? Does your car vibrate/shake? Or is it just a noise without any physical affect? And where is the sound coming from?

Please be more specific.

cv129

Possibly loose wheel well cover because of missing plastic tabs? I don't know, random guess.

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Setrab | RE-71 | SPL | JRZ | Nismo | ARK | Whiteline | RacingBrake | CJM Oil Pan | Ti shield

lkh5650

Thank you for your reply

it was hard to tell... It was periodic, every 1 second or so, very loud knocking sound and in between the period the sound was still there but not as loud/pronounce
I didn't feel extra vibrate/shake
I think it was coming from somewhere between mid center to back center of the car..

lkh5650

I am not so sure, but I dont know why it would only occur at high speed...if thats the case

cv129

Are you on the OEM plastic shield or the Z Speed aluminum shield? When my OEM shield gave and the middle 3 tabs were gone, disturbed air flow flapped the OEM under shield but only at a high speed, and stopped as I slowed down.

Sorry that's all I have to contribute, best of luck

__________________
Setrab | RE-71 | SPL | JRZ | Nismo | ARK | Whiteline | RacingBrake | CJM Oil Pan | Ti shield

lkh5650

are you talking about the plastic cover that you take out for oil change...? that is not oem cuz i had to replace it.. lol everything else is OEM tho

i am gonna check if any plastic shield is flappy tmr..

Thanks

GMB14U2NV

I would check the front end for missing plastic fasteners and or bolts. In particular the 3 center plate/guard fasteners. If the 3 center points are not present - the cover will bounce against the under engine frame and resonate to the mount points sounding like middle of vehicle.

If it's aftermarket under shield - get some heavy duty fasteners that hold the center - 3 of 'em. (AutoZone Medic Isle - package of 4 is what I saw)

If you only have the outer edges of the plastic under shield or aluminum shield fastened and not the center - my friend - it's gonna bounce against the sub frame. I learned this after doing my first oil change and thinking I was slick by leaving the 3 fasteners out for "next time...."

Got to 80mph on a toll road here and thump thump thump thump..... then when I slowed down thinking WTF???? it stopped. After the second day of the same sound, I put the center 3 back in and have never heard the thumping since....

old guy

Silverstone

The people advising to check under the front end for missing fasteners are spot on.

When you go above a certain speed and generate a certain wind speed, the loose plastic piece will catch and scrape the ground. As you slow and the wind speed decreases, the plastic piece can return to its original position.

lkh5650

Hey, thank you for your reply.

Are you talking about the plastic shield shown here?

GMB14U2NV

Yes that's the shield.....
I'll get some pictures of my under guard and give you some points to check.

Sent from my SAMSUNG-SM-G935A using Tapatalk

NISMO IX

LOWER COVER CLIP for 2014 Nissan 370Z|01553-2DR9A

https://www.z1motorsports.com/front-...321-p-502.html

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2014 370z Mag Blk 6M "KOKURYU" (Black Dragon)

lkh5650

Thank you so much guys... I ordered these clips (from the first link, it was cheaper with the shipping cost)

I will try to lift the car up abit using two jack and see if these clips were missing. if they were, I will just put those on when these are delivered. I hope that was really it!!

I will give yall an update

Ghostvette

I found the same clips on EBay for about $5 for 75 clips w/free shipping. Google search by PN....

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