Good afternoon 2010 4Runner owners...

I was wondering if the new 4 runner still has that rotten egg smell after you accelerate real fast... I have an 05, and when i have the windows down and when i accelerate real fast (from 30mph, to 70mph) It smells like horrible rotten eggs, and it is embarrassing when you have friends in the car, and ask what the hell died in your car. I was wondering if it does it still smell like rotten eggs, or did they finally resolve that problem?

If it still does stink, then Toyota has Failed....

no egg smeill in mine and I drive with the sun roof and read window down all the time.

If it's the same problem the 4th gens have its your catalytic converter..I had the same problem when I had my rear window down until I cut my exhaust off at the axle. It happens with some and doesn't with others.

ditto.

Its a common problem among almost all cars. If you buy discount gasoline, the smell is from the additives. I've had it happen from my '85 nissan 300zx all the way to my mother's 2008 avalon (when she bought the discount a few times).

Nothing wrong with the truck.

*However, if the smell is overpowering even after buying decent gas, it could be your cat. Although a cat failing in just a few years is uncommon.

Been driving every nice day with all windows open (including sunroof and rear window). We definitely get a huge whiff of sulfur a few seconds after a hard acceleration or when going up a hill. It's definitely the fumes coming in. Not sure how other folks are not experiencing this whenver I experience it all the time (however, it ONLY happens while driving with the rear window open).

Shouldn't be embarrasing for you though because the smell quickly dissapates.

I get it when entering the highway under hard acceleration. Usually have the driver's side window open as well as the moonroof. It lasts maybe a minute or so. Definitely annoying. I wonder if I should be concerned? Seems strange to me as I have NEVER had this problem with the other dozen or so new cars I have had in the past. And I buy Shell gas exclusively, which should be considered higher quality gas. I have about 1600 miles on it so far.

It's always funny when the fan boys come out with their excuses for Toyota's problems.It's normal for the car to smell like a rotten egg.Yeah normal for Toyota.

Smells Bad to Me......I get it every time I have to accelerate hard. 2nd Toyota I have had that had this issue. But I have to agree with the statement above......your not supposed to say anything negative about the 4Runner......its the "perfect" vehicle. Pay no attention to that loose lumbar support in the drivers seat, the fact that the car sometimes lunges forward when downshifting and the fact that any strong crosswinds will blow you all over the highway.

You guys do know how fuel injection and emission systems work right?

First off, when you accelerate aggressively, your ECU goes into OPEN LOOP, causing your mixture to go excessively rich and the catalytic convertor may not be able to keep up with the increased exhaust volume and pollutant levels - the egg smell is a result of a rich mixture and pollutants. All cars do this. My Prelude did it. My s2000 did it (a level 2 LEV by the way), my WRX STi did it, and the 4Runner does it.

Its only more noticeable because you have a large open window right above the exhaust!!!!

This also happens during cold starts - as your catalytic convertor has not reached operating temperature, thus not effective at reducing the pollutants - hence the smelly exhaust on cold mornings. This is why many cars have the air injection systems that kick in on start to lean out the mixture....not sure if the 4runner has it though.

Simon, thanks for the reality check, good explanation. (All my life {long time btw} I've known not to drive with a tailgate window open).

To expect exhaust gasses to a) not get back into the car and b) not stink, is ..... well ...... unreasonable.

I tried this yesterday just to see, and yep, it stunk, so I closed the back window.

Patient: "Doctor, it hurts when I do this"
Doctor: "Don't do that".

I refer you to simonj's response. Has nothing to do with fan boys. Has to do with engineering of the exhaust system and good fuel.

I'm just saying if I can take my power commander and fine tune a fuel map for my raptor 700, why can't Toyota get their mapping right so it's not running excessively rich.

Because Toyota's map has to take into account a very broad spectrum of driving conditions - ranging from Colorado high altitude summers to briskly cold Canadian prarie winters. Those two climates demand very different fuel maps, so the Toyota factory map has to be jack of all trades.

Yes, you can "fine tune" your raptor 700....for the conditions where you are driving, but what happens when those conditions drastically change?

I speak from experience as I had a custom tune for my WRX STi. It was optimized for summer driving. As soon as the colder winter temperatures hit, the car would drive like crap and overboost (due to colder, denser air), so I had two maps made - one for summer, one for winter.