Whats that smell?

Ok so on startup i get an exhaust smell.....as I start to drive, slow speed, window down,,,I get the smell. I think it may be a leak...but it seems to go away after the engine heats up.

 

Exhaust mods are Cobb DP, Grimmspeed flex UP, all else is stock. I did use new gaskets when I re-installed the manifold, up and dp from Grimspeed.

 

Any thoughts?

Cats or no cats? I noticed that when I went catless I get the smell when I first start the car or go in reverse.

You have a leak and the reason it goes away when the car gets warm is... THE METAL EXPANDS and closes the gap.

 

Roll by a exhaust shop in the seedy part of town and give em $30. Problem solved.

You have a leak and the reason it goes away when the car gets warm is... THE METAL EXPANDS and closes the gap.

 

Roll by a exhaust shop in the seedy part of town and give em $30. Problem solved.

 

 

Thats what I thought too...but I did take it to a shop and they said I didn't have any leaks.

 

I guess I should take it else ware.

Thats what I thought too...but I did take it to a shop and they said I didn't have any leaks.

 

I guess I should take it else ware.

 

My only guess is that it was not cold when they looked for it? (I mean exhaust cold to touch not cold out today;))

 

Can I get an MSprank opinion here? (I will pm him the thread)... He spent some time in an exhaust shop in his youth. He is very knowledgeable.

Could just be the cat heating up. Not sure if you are catless or not.

 

If you are catless, or OCD like me, I would get a helper. Put the car on stands/ramps. Something so you can get to the collector/uppipe connection as well as the DP/CBE. Make sure the car is cold. Get under and have someone else start the car. First while it is cold (you don't have much time) check with your hands for air leaks (should feel like a sputtering at the flange). Second, look for condensation at the flanges. Water will come out with the air if the car is good and cold (best to get it hot, then let it cool this causes the moisture). Normally this moisture comes out your tail pipes, if it comes out before the tails you found the leak.

 

Very small leaks are a bitch. It sucks, but in the end if it is flanges, good old "copper" gasket maker does the trick.

Could just be the cat heating up. Not sure if you are catless or not.

 

If you are catless, or OCD like me, I would get a helper. Put the car on stands/ramps. Something so you can get to the collector/uppipe connection as well as the DP/CBE. Make sure the car is cold. Get under and have someone else start the car. First while it is cold (you don't have much time) check with your hands for air leaks (should feel like a sputtering at the flange). Second, look for condensation at the flanges. Water will come out with the air if the car is good and cold (best to get it hot, then let it cool this causes the moisture). Normally this moisture comes out your tail pipes, if it comes out before the tails you found the leak.

 

Very small leaks are a bitch. It sucks, but in the end if it is flanges, good old "copper" gasket maker does the trick.

 

Thanks Ill give it a try

 

DP is catted UP is catless with a flex section

You can also use smoke (nothing on fire, obviously) to see if there's a leak. If you get a sudden change in smoke direction in a specific area, you've found your leak.

 

+1 for the copper gasket material. It's not ment to go on exhasust applications, since the heat rating is around 400 F, I think., but it still works great as added protection. I re-used all of my gaskets (not reccomended) with the copper gasket paste. No leaks for 10K thus far.

Permatex Ultra Copper, Sensor-safe, high temp rtv silicone gasket maker. Highest temp rating available at +700deg. Max strength for high torque engines. There is nothing that withstands the heat for exhausts better.

 

Not my first choice (it is a bitch to separate and clean), but it does work.

^ yep, although it almost smelt like burning marshmellows the first few days . At least mine did

^ yep, although it almost smelt like burning marshmellows the first few days . At least mine did

 

MMMMM Marshmallow Exhaust Paste Cookies...

MMMMM Marshmallow Exhaust Paste Cookies...

Yeah, I probably killed a few brain cells smelling my exhaust, with my window's down, in our parking garage...