FAQ: The Exhaust Thread

An exhaust leak is going to make lots of noise. You'll hear it long before you see it.

no noise. It sounds great. I am actually really happy with the sound and feel of the new exhaust. Just that smell... I will try plugging the 2 holes and see what happens.

If you don't hear any ticking from the downpipe, it's not leaking exhaust. Could be smelling burning oil or fuel somewhere on the engine. Check for gasket/line leaks. Or maybe those holes are letting in fumes when the wind blows from behind.

That's what I was thinking AA. Charlie, did you remove the CAT? I can tell you that the exhaust is going to smell pretty rich if the CAT is gone, especially in the morning. I love the smell of mine in the morning Plus, it's going to take awhile for that new downpipe to burn off all of the oil/impurities inside of it and out. Hence the smell. My headers stunk for like a month.

Any little tiny hole into the cabin is a potential smell leak lol.

From behind, my exhaust smells like gas burning in the "7th cylinder". Just ask matt270avian.  

LOL! Love it. I like it in the fall, when it's chilly in the A.M. The "fog" that comes from the tail pipes burns your eyes.  

AA wrote:

From behind, my exhaust smells like gas burning in the "7th cylinder". Just ask matt270avian.  

Yeah, smelled somewhere between hot ceramic and oil burning.

matt270avian wrote:

Yeah, smelled somewhere between hot ceramic and oil burning.

 

I'll show you a pic of my oil level at next change (fresh rebuild = zero oil leak/burn). Most younger folks haven't enjoyed the smell the uncatalyzed, fuel-rich exhaust Abaddon mentioned. Maybe you have, Matt, but I can't think of anything other than gas that's being burned.

AA wrote:

I'll show you a pic of my oil level at next change (fresh rebuild = zero oil leak/burn). Most younger folks have never enjoyed the smell the uncatalyzed, fuel-rich exhaust Abaddon mentioned.

That makes total sense. As far as I'm concerned, that's one of the best scents on the planet.  

BIG difference between burning oil and "go fast" fumes

I had to run my '78 Thunderbird rich in the winter so it would stay running when it was cold. She smelled great!

BTW, best way to tell if you have a tiny exhaust leak is to pull in between two buildings and let your car idle. It kind of amplifies little ticks that you otherwise would be unable to hear.

AA wrote:

I'll show you a pic of my oil level at next change (fresh rebuild = zero oil leak/burn). Most younger folks haven't enjoyed the smell the uncatalyzed, fuel-rich exhaust Abaddon mentioned. Maybe you have, Matt, but I can't think of anything other than gas that's being burned.

To be fair, the oily smell could have been coming from me (remember the sludge buildup due to possible leaking valve covers? not to mention the fresh oil change 2 days earlier). but the hot ceramic smell (best way I can describe it) was definitely coming off of yours.

Ahh, I know what it is. I smell it sometimes when I get the headers really hot. It's the DEI Titanium wrap. The smell never burns away completely. Their website says it's made from pulverized lava rock!

What is the vent looking thing on the passenger side of the trunk? What's the purpose?

The system used to be called Astro Ventilation, or something like that. Since the HVAC fan is on pretty much all the time it is what lets air escape when everything else is closed, allows air to circulate through the car.

And the tube next to the vent? Same purpose?

I am getting exhaust smell in the cabinet, I dont have my trunk lining/insulation in the car at the moment, so I'm wondering if its because theres nothing in front of the vent?

Im going to try putting the lining back in and see if it takes care of the smell.

charlieRobinson wrote:

And the tube next to the vent? Same purpose?

I am getting exhaust smell in the cabinet, I dont have my trunk lining/insulation in the car at the moment, so I'm wondering if its because theres nothing in front of the vent?

Im going to try putting the lining back in and see if it takes care of the smell.

Check entire exhaust system for leaks.

Leaks on top may be hard to spot, look for soot or areas that look blown clean.

Maybe a manifold crack.

Can anyone link me a sight to find some nice headers for my 96 riviera supercharged?

I don't have the lining in my trunk right now either and I don't get any exhaust smell inside mine. Must be an exhaust leak as Albert states?

99Rivman wrote:

I don't have the lining in my trunk right now either and I don't get any exhaust smell inside mine. Must be an exhaust leak as Albert states?

I pretty much guarantee you it's an exhaust leak.

The Riv ventilation system runs pretty much all the time unless you turn it OFF. Air comes in from the cowl vents and to some extent thru the doors (keeps them drier inside). Air pressure at the cowl vents is high, air is forced thru the grille and slips out under back of the hood (esp if your gasket is missing) and gets sucked in the cowl vents. Air pressure at the trunk vents is quite low, venturi effect of air blowing past is to blame/thank. So if there are perforations in the car floor and an exhaust leak almost anywhere then fumes will get sucked in because, while in motion, the trunk vents are sucking air out of the cabin (the source being primarily from the gap between rear seat back and rear seat bolster). So the cabin vents and any gaps or perforatons in the cabin generally draw air in. If you crack open the sunroof that creates a low air pressure point in the cabin, that draws air out.

If you smell exhaust in the car, it pretty much has to come from somewhere between the exhaust manifold gasket and the rear mufflers.

So yes, you really should go inspect.

Albertj

charlieRobinson wrote:

My exhaust was welded together and now I have this doubt that there may be a leak..

Here's a clue from previous page. Before you had the exhaust work done, there was no smell. After, smell. It's not a guarantee the leak is coming from the welded areas, but I'd start there for sure.

Has anyone heard of corsa performance or heard them on a 3800 gm

Yes, they are based here in Ohio. I sent an email to CORSA in mid '04 about helping me create a custom exhaust system, even included photographs of the underbody & exhaust system on my car. I received a reply from Jim Browning Jr. basically saying they "really don't know if it would work..."

I think CORSA was more interested in supplying parts to Corvette owners, or at least that was the impression I got. Maybe things are different now?

Johnny5, just so you dont get your hopes up too much, the 3800 is not an extremely good sounding motor.

Sir Psycho Sexy wrote:

Johnny5, just so you dont get your hopes up too much, the 3800 is not an extremely good sounding motor.

Trust you me buddy I know from experience it reminds me of 100k bees in a tin can angry as hell thats why im dying for responses ... over YouTube grand prix sounds great