nitrodude

Hey guys, I bought this camaro used a few months back and ever since I've had it its made this noise.
It does it while driving in any gear, cluth pushed in or not, does it while stopped emergency brake on and in neutral (Its a manual) and revving it to 2-3k rpm it makes the noise.

It sounds like its coming more from the passenger side undercarriage.
there is a part of the exhaust with a heat sheild on it right there but it doesnt seem loose? its also right at the end of where the transmission bell housing is (I really hope its not trans related)

I peeked around under the car and couldnt find anything loose either. I'm at a lose as to what it could be.

The sound while driving sounds almost like grinding gears while shifting. Its loud and obnoxious. I really hope I can fix it! If anyone has any suggestions please let me know what to check! Thanks!

maxharvard

How many miles?

My guess is a loose heatshield. It may not seem loose now, but I bet if you put it on a lift and revved it up you'd find the loose piece. Pretty common actually.

nitrodude

Its got about 125k on it. I drove it around yesterday and listsed a little more, it seems it does it (Or i can hear it) a lot from 1-3rd gear and about 1-3k rpm. I cant hear it in 4th-5th gear (probably because of wind noise baffling it)

How do I check the heat shield? Theres what looks like wire mesh on the bottom of the exhaust that looks like its crimped on, and on the top between the exhaust and floor pan on the passenger side theres a metal plate that didnt feel loose but i didnt see any bolts or anything to tighten?

maxharvard

You'll need to get it up on the air, have someone rev it up till it makes noise and hunt it down while you can still hear it.

nitrodude

Okay, But assuming it IS the heatshield, How do i fix it??

maxharvard

Reweld it or remove it.

nitrodude

How would I go about removing the upper heatshield between the exhaust and floor pan?
I take it the one on the bottom of the exhaust would just pry off with some effort.

maxharvard

You'll have to remove that pipe from the car to get at it.

nitrodude

Alright, FInally got around to getting a couple jacks and raising the whole front of my car to crawl under it (No ramps)

Found the rattle, Its definitly from the cat. I dont think its a loose heat shield, Pushed and touched them both and no change, It sounds like something is loose inside the cat.

So to replace it, Was looking and it looks like the end of the exhaust unbolts, but it looks welded to the headers?
Is this something I can buy/replace myself? Or Does the cat need cut/rewelded on this car? Not 100% familiar with exhaust systems on camaros, or any car for that matter.

My car has always had a little bit of smoke from the exhaust and smells like gas from the exhaust (running rich?), could this be a result of a bad cat as well?

I've read a lot of people just remove them, Is this better then keeping it? Theres no emissions tests here in FL.

Whats the best thing to do in general, Buy a new cat? Replace it with straight pipping? Or?

73CamaroLT

iTrader: (8)

Try something first. Hold the o2 sensor and then shake the cat. I have a rattle and it ended up being the o2 sensor. A stretch but it is a possiblity.

nitrodude

Was it loose?
I think theres loose chunks of metal in the cat, It's a REALLY loud rattling noise. Sounds terrible, And I'm tired of hearing it lol.

nitrodude

Well, I found a local exhaust shop and brought my camaro there.

He cut it out, and welded a pipe in its place.

There was literally damn near nothing left in the cat, Just a big chunk of metal that was loose in there. Im glad it didnt clog up the rest of my exhaust.

Drove it home with no rattles, I'm happy.

All for $30+$10 tip. I'll be going back to that shop in the future to get a cat back exhaust put in.

nitrodude

I know most of you will say its the "placebo effect", and it very well might be.
But, I feel like it does have a little more power then before, Chirped the tired a few times driving home, never did before lol

The shop was only 5 mins from my house, so it didnt take much of a drive, it idled at the shop for 5-10 mins before I left as well, Havnt gotten a CEL, YET!

If I do, Whats the cheapest thing to do to get it to stay off? I've heard of spark plug foulers to space the o2 sensor out farther? But also heard its not a guaranteed fix.