Burning plastic smell.

[terryk2018]

I have over 3000 miles on my 2018 premium, and I smell something like burning plastic. It happens in different areas, but usually under load, like a steep hill. I thought it would go away, but it has been there since new. It does not smell like brakes, oil, or tranny fluid. We don't smoke.

 

[nb rob]

is your back window down when you smell this? If I go up a steel hill with the rear window open, I'm guaranteed to smell it.

otherwise, this is a common question-- and you'll find it strongest by the passenger rear tire.
The consensus is that it's normal, with plenty of speculation. I think it might be the exhaust isolator closest to the muffler...

 

[baldrik78]

I'm at 19k miles and I've gotten the same thing since day 1. Definitely strongest near passenger side rear.

 

[1996_Valencia_Owen]

It's definitely the exhaust rubber isolator.

The smell weakens over the first year (esp after a hot summer) but doesn't go away completely. A very odd minor issue. I feel like placing the isolator a cm further away would help it be just far enough away to stay cool, or use a diff rubber type.

 

[4runr4eva]

is your back window down when you smell this? If I go up a steel hill with the rear window open, I'm guaranteed to smell it.

otherwise, this is a common question-- and you'll find it strongest by the passenger rear tire.
The consensus is that it's normal, with plenty of speculation. I think it might be the exhaust isolator closest to the muffler...

If I leave the back window open and floor the accelerator, I get a strong ammonia smell. I believe its from the hot exhaust hitting the cats. First time I smelled it I didn't know what was happening. I just gasped and held my breath for a while. :shocked:

 

[Snickel Fritz]

I noticed the same thing while idling in a parking lot, wafting up through my opened driver's door. I placed my hand outside the door, and could feel what seemed to be hot exhaust blowing out to the side from under the truck where I imagine the exhaust manifold-to-cat gasket is.

Is anyone else experiencing this? Is it normal?

 

[MattX014]

2018 OR PREM 4k miles

I've got 4k miles on my 2018 OR Premium as well, the smell still comes around on occasion but has gotten alot better in the last 2k miles. I feel its normal and getting more and more rare. I'm not too worried about it.

 

[blanchard7684]

Had this on my 16 SR5 Premium and on my 18 Limited. SR5 was worse for some reason.

 

[chester4Run]

I've got 92K miles on my 2011 and no such smell that I've noticed. So there's some hope it will go away with time and miles. Hang in there folks...

 

[Bossman]

Did you take the bubble wrap off of the entire exhaust system after you bought your new 4Runner? The packaging that some of these automotive companies use during shipping! :jk:

 

[Vermilion]

Did you take the bubble wrap off of the entire exhaust system after you bought your new 4Runner? The packaging that some of these automotive companies use during shipping! :jk:

Honestly it wouldn’t surprise me.

I have heard of driving over plastic bags on the road sometimes sticks to the exhaust and melts.