Please help me find this underbody rattle
 

Before I go completely insane.


I'm hearing a rattle that sounds like it comes from the front drivers side of the car when I go above 65. It's not completely constant, it comes and goes but I'd say every 10 seconds or less so it's frequent enough to investigate.

After sitting in the passenger seat however, it sounds like it's coming from the rear drivers side :sigh:

Things to note, I have the JDM underbody panels and I did remove my front bumper once to install my horns. I don't drive on the highway too frequently so I can't determine when this noise started.

I did have issues with my front bumper alignment but I've fixed that with no fix to the rattle. I've rechecked the JDM panels and all bolts/clips are good and in place. I will note that there's a bit of flex on the gas tank panels towards the inside center but no one else has seemed to complain of underbody panel rattle so maybe that's a non-issue.

Any suggestions on things to check?

Maybe I can get the dealership to let me check it out on a lift.


Edit: Oh and while double checking the front bumper today I heard a rattle. There's a vented panel there that can be popped out. I did that and this guy fell out....(not the source of my high speed rattle)

http://i.imgur.com/s0i1uZR.png

[ame]http://youtu.be/evgEJlOPoeo[/ame]

LOL when I saw this I thought of Michigan J Frog. I had a noise coming from rear passenger side I took it to dealer they said it was a loose plastic shield for something.

I've found on my car that the "fabric" underbody panel started to get loose around the mounting bolts after a few uninstall/install cycles. I ended up putting washers on the bolts that hold it on to get the tension back when I mounted it.

:bellyroll: To be honest my first reaction when the frog fell down instead of a rock, as I was expecting, was of pure terror :bonk:

I bet anything mine is a plastic shield somewhere, hopefully they let me check it on the lift.


Hmmm that's a good thought. I've only removed them once and that was to put on the JDM panels. As I said, the bolts for all those panels seem quite secure...but the rear panels (gas tank panels) would benefit from more clips/bolts.

I had a rattling from my skid plate. Jack up you car and "punch" the skidplate around each screw. If anything is a little loose it will vibrate at high speeds.

I had this one and used neoprene (rubber) washers from Home depot on each bolt except the 2 that also go through the plastic panel that runs to the back of the car.
@Laika also check out this thread... http://www.ft86club.com/forums/showthread.php?t=34465 When I first noticed this on mine, I had a hard time telling exactly where the noise was coming from.

My BRZ had lots of rattles. When we first took it on a long interstate trip, there was a tap tap sound from under the car when cruising at 65-75 MPH. On and off. It was somewhat soft and at first I thought it was from the truck next to me, but came to realize it was from under my car.

This will sound crazy, but I have since applied caulk around the plastic wheel wells followed by undercoating spray to stiffen the plastic up. Then noticed, as others have pointed out, that the under body panels of the car have too much play and move up and down. Caulk in just the right places corrected that too.

Since then, no odd sounds or taps. BRZ is quieter.

If I understood correctly, is it telling me to do what I show in the pic below?


Well I did this (obviously hah) and I think ....IT'S FIXED! Whether this is what I was supposed to do or not, THANK YOU. Now I can start reversing my insanity.

Another rattle solved by FT86club.com :happy0180:

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I'm glad that worked for you, but it wasn't exactly what I meant. I was quoting whataboutbob in regards to the under panel rattle (under the car below the transmission). The link I posted is related to the rear fender liner rattle. I found that removing each clip and placing a rubber washer between them and the liner cured this one. If removing a screw or clip (what it looks like in the picture) made your rattle go away, than the rubber washer trick might work for you. There is another thread with more detail, but if you want more info just shoot me a pm, and I will walk you through it. It's pretty easy...

Now I'm more worried because I didn't have to remove a bolt/clip to do what I did. Maybe I was missing one and having a rubber washer behind it would have helped after all. If I am missing one, then it's gone from both sides.

The noise is gone but I still don't consider it fixed per se. I'll try out your suggestion and see what I can do with the washer.

Don't worry. You didn't lose anything. I went up and looked at mine...I see what you did now. You just flipped the liner to the outside. The hole where I thought you pulled a clip/screw out of is fine. My car came with mud flaps that cover most of that area, and it threw me off. Take a look above and around the tire, and you'll see that the plastic liner inside the fender is held on with plastic clips (push pins). One at a time, pull the pin and pop the clip out, slide a rubber washer under the head of the clip, put it back in and push the pin down until it clicks. You'll need about 10 neoprene (rubber) washers for each side of the car in a 5/16" or 3/8" size. $5 should buy all you need in the nut and bolt section at Home Depot.

I was going to suggest you check if this area was rattling at higher speeds. @kanundrum was getting some rubbing at freeway speeds because a clip in the fender liner wasn't put back; oddly enough it only rubbed when in clean air (when not drafting).

To fix the underbody panel movement, get the complete underbody panels kit. The screws were designed to allow the panels to overlap and only then is it a snug fit.