WTH is that smell? Exhaust with the rear window open

[Carl Fisher]

Been meaning to post this for a while now because it seems to be getting worse.

I've had to stop dropping the tailgate window when I'm under any sort of load. A smell that I can only describe as sour that is different from any normal exhaust smell I'm familiar with fills the cabin. My wife says it smells like peroxide (think hair perm smell)

If I'm just cruising, it's fine. But as soon as I'm under load of a climb or towing it's just obnoxious.

Any thoughts on why this smell could be developing? I don't recall it being there prior to the last 6 months or so and I can only imagine what it smells like to someone behind me.

 

[DisguisedRope]

Not sure why it smells like it does, I usually equate it with rotten eggs/sulfur, but it's definitely the exhaust. Most fix this by having the tailpipe turned out the side instead of straight back.

 

[ChaosStarter]

Been meaning to post this for a while now because it seems to be getting worse.

I've had to stop dropping the tailgate window when I'm under any sort of load. A smell that I can only describe as sour that is different from any normal exhaust smell I'm familiar with fills the cabin. My wife says it smells like peroxide (think hair perm smell)

If I'm just cruising, it's fine. But as soon as I'm under load of a climb or towing it's just obnoxious.

Any thoughts on why this smell could be developing? I don't recall it being there prior to the last 6 months or so and I can only imagine what it smells like to someone behind me.

It's the exhaust. When the cats get heated up under load, they tend to put out a rotten egg smell.

This is why Toyota says not to drive with that rear window open. A low pressure zone is created when driving behind the truck and the air tends to just tumble and circulate the exhaust fumes into the cabin.

I see people with 4Runner's driving around with their dogs head out the back, and I feel just terrible as their slowly just killing their dog.

 

[black4vcobra]

Open your front windows a bit and the airflow through the cab should keep the fumes out of the truck.

 

[LOSTR4]

Or you can lop-off the rear resonator and buy a 90* exhaust pipe and have it turn out to the side to eliminate the "rotten-egg/exhaust" smell when driving with the rear window down...easy fix!

 

[Carl Fisher]

Actually opening a front window makes it worse. It creates a vacuum into the cab.

I've considered dumping out the side instead of out the back when I finally pick an exhaust system.

That said, it's good to know that's the normal smell for a Toyota exhaust. It's definitely distinctive from any other vehicle exhaust I've had.

 

[4by4th]

I've always wondered if the rear spoiler that some 4Runners have help with this or not, mine never had one.

 

[LOBO79]

I've always wondered if the rear spoiler that some 4Runners have help with this or not, mine never had one.

Nope

 

[alia176]

When I run at higher speeds with the rear window being open, the cab will get warmer and the smell of combustion is strong.

 

[Carl Fisher]

I've always wondered if the rear spoiler that some 4Runners have help with this or not, mine never had one.

Nopers

 

[PaulB-2006 T4R]

All guys fart, right? Well so does the 4Runner and most Toyotas for that matter. The smell is normal. I like to hit the gas pedal hard in front of a convertible.

 

[M1911]

There is a reason that the manual tells you not to drive with the rear window down. Even if the exhaust doesn't smell like rotten eggs, it is pulling carbon monoxide into the cabin and that isn't good for you.

 

[BlackWorksInc]

I have had less of an issue with exhaust smell since I lopped the resonator off and had it dump downwards after the axle. The only times I notice exhaust fumes now is at lower speeds with the rear glass down.

 

[CXS]

My tailpipe is turned to the side, resonator removed and it still sticks under load. Spoiler on and off make no difference. I just put it up if I'm going to be driving aggressively.

 

[The Grand Wazoo]

All guys fart, right? Well so does the 4Runner and most Toyotas for that matter. The smell is normal. I like to hit the gas pedal hard in front of a convertible.

my kids know the smell well and love saying "hahaha the 4runner farted hahahaha" whenever it happens.:biggrin1:

 

[rdswriter]

I drive as much as possible with all windows down and sun roof open. Even at highway speeds I don't notice any smell. That being said... I think I've only driven once with only the back window down and that was cruising at less than 40mph. I didn't notice any smell...

 

[Carl Fisher]

my kids know the smell well and love saying "hahaha the 4runner farted hahahaha" whenever it happens.:biggrin1:

lol!

 

[RPS13]

Maybe mine doesn't do it, but I've never ever smelled a gasoline powered car that gave off a rotten egg smell. The slightly "nose stinging", somewhat chemical smell is NOx that's not getting processed by the cat.

Cars just coming off a racetrack with a cat put it out really strongly.


I kinda like the smell to be honest, maybe because of the track thing.

 

[Lolrax]

Typical Toyota smell. 2 sequoias, and 3 4Runners in the extended family and they all have it haha. We are always lending them to eachother when people have to move, need an extra car or whatever and they all have it.