What should a normal FZJ exhaust gas smell like?

[e9999]

this other thread about gas smell made me wonder the following:

I can't quite describe this accurately yet, and I have not done systematic tests, but my exhaust has a bit of a "sour" smell to it, at least right after starting. But then again, I don't know what it should smell like if all is well. Never noticed any strong smell on my Accord -maybe cuz there is much less coming out...

I have the impression from reading that a "sweet" smell indicates the presence of coolant and a gas smell, well, should be gas.

Sooo, what does your exhaust (no kindergarten puns here, pls, remember we are cleaning up our act here in Tech ) smell like?
What should it smell it like in a perfect world?
And what does a sour smell indicate -if anything?

Anybody?

 

[Montana Cruiser]

I brought this up awhile back and most agreed that a slight "gas" smell was normal. In my case I could really notice it at start up in the morning after the truck was completely cold. I have a remote start, so I would fire it up right before getting out there and it smelled"gassy" to me. As long as you arent smelling coolant, I think its normal.



> After reading the other post about this, I wanted to clarify that my gas smell goes away quickly as the trucks warms up and I dont get any smell when starting the truck warm the rest of the day, only cold after sitting for many hours.

 

[Scamper]

e-

A "sour" smell is not the smell of antifreeze burning--at least that's not how I'd describe it. Antifreeze is sweet smelling when in it's un-burnt state. But when you run it thru the engine and cat, it smells really bad--I'd describe it as "acrid"--sharp and nasty foul smell.

I also don't know if you'd be able to detect it in your exhaust by smell if only a very tiny amount was getting by the HG. But who knows...maybe under those conditions it just smells "sour"

 

[NorCalDoug]

You're just trying to trick me aren'ty you? I'm not sticking my head down by my exhaust!



Edit: Honestly...I don't smell anything odd.

 

[RavenTai]

Mine smells rich on cold start especially in the winter especially noticeable in the closed garage, does not smell like much of anything after that though I have not got down there and got a direct sample.

 

[e9999]

Mine smells rich on cold start especially in the winter especially noticeable in the closed garage, does not smell like much of anything after that though I have not got down there and got a direct sample.

well, what's a "rich" smell like?

 

[landtank]

well, what's a "rich" smell like?

Not sure, but a "Rick" can smell pretty damn bad at times from what my wife tells me.

 

[PACNW96]

I bought my cruiser a few months ago and I noticed when it was cold it really had a strong exhaust odor upon initial startup, even more so than my 95' 4Runner. As also stated above this odor diminishes a lot once the vehicle warms up. I initially thought that I had a bad catalytic converter or an emission problem because the smell was very strong, but the smell went away after it warmed up. Good to know I'm not the only one.

Russell

 

[schum4]

My exhaust smells TERRIBLE most of the time - whether it's hot or cold. It's not a gasoline smell and it dosen't smell sweet. I did notice that on rare occacions, when the truck idles smooth, the exhaust smells better.

Can anyone confirm what might cause a strong acrid/poisenous exhaust smell? I just hope it's not the HG leaking coolent.

 

[LX_TREME]

You're just trying to trick me aren'ty you? I'm not sticking my head down by my exhaust!



Edit: Honestly...I don't smell anything odd.

BWAHAHAAAA... that cracked me up.... I got JDM dual exhausts cat back system... it smells like Victoria Secret Man cologne.. LOL

 

[CharlieS]

It is the stuff that doesn't smell that is going to give you a headache or kill you if you keep sniffing the exhaust - carbon monoxide.

"Rich" smells like gasoline.

Stinky? I can only guess that it is a problem with other unburned substances. Sulfur is one stinky exhaust product that comes to mind that has a nasty smell.

However, I think if your catalytic converters are working properly, catalyzing these other gasses, then you won't smell these "stinky" smells.

It might smell stronger at startup since the catalyst has to get up to temperature to work properly. It is not filtering the exhaust, it is causing a catalytic reaction, converting nasty stuff, to less nasty stuff. The catalyst needs to be pretty warm to work - if I recall correctly.

Found this on a quick google search:
"Catalytic converters are usually mounted in the exhaust pipe near the engine and look like a wide place in the pipe, roughly 8" long and about 3 times as wide as the exhaust pipe itself. Just like most chemical reactions, catalytic converters work better when hot, so they are placed near the exhaust manifold so they will warm up quickly. When your car is cold, the catalytic converter does nothing to your exhaust - it has to warm up to an operating temperature of about 300 ° C to work effectively. This means on short trips (< 5 miles or so) the catalytic converter does nothing to clean your exhaust. The operating life of a catalytic converter can be shortened if it gets too hot, which necessitates it being a foot or so down the exhaust pipe."

Charlie