NoOneBetter
Member
I've got the smell too just like everyone else on my 15 TEP with ~30k miles. Smell just like burning tires.
I've got this on my 2014 SR5. My wife actually mentioned the smell the other night as she was removing my son from his car seat on the pass. side. Seems to be no real answer yet. I will investigate in full. Def smells like hot rubber. I have done all my own maintenance, fluids, grease, etc. since day one. i will report back any findings. My guess is exhaust hangers heating up.
I have a 2017 off road and like yours, under load the vehicles smells so bad I can not keep the windows open or it will choke the passengers. Toyota Canada is going to inspect it next week. it always happens under hard acceleration, always.I experience the smell every day, as I drop my kids off at daycare. The daycare is on top of a hill, so I am always putting some load on the engine, then getting out, and going over to the rear pass side door to get my daughter out of her car seat.
Along with the smell, my muffler ticks, snaps, crackles, and pops like crazy, once the 4runner has been turned off. I have been under the 4runner many times with a flashlight, while the smell was occurring, but could never find anything on or around the exhaust or muffler that would cause this.
I have noticed the smell only occurs after I have put load on the 4runner, like driving through a parking garage, or driving up a hill. Out of curiosity, I measured the muffler's temp with an IR thermometer after driving up a hill, and it was around 320*F. During normal operation at idle it is around 215*F.
I have read threads on the FJ Cruiser forums about the same smell. One guy even cut open a muffler and this is what he found:
Thread: Anatomy of the OEM Muffler. - Toyota FJ Cruiser Forum
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So after much obsession, I believe is normal, and most people just don't notice/care about it. Here is my conclusion on the smell.
1. The Smell is from the inefficient/poorly designed muffler, that can get super hot, when even a moderate load is put on the engine.
2. I have never found any trace of anything burning on, or around the muffler, or exhaust pipe, so I believe that is just the smell of muffler itself at 320+*F.
3. Replacing the stock muffler with a straight through design one would eliminate the smell.
Super perplexing. Have this on my 2018.
I suspect the exhaust hangers. The flaw in logic is that not seeing melted spots on them means they arent burning.
The way heat would transfer would be through the metal hanger pins.
So to tell it's burning you might have to pull a rubber hanger off the truck and inspect the inside.
Might also be worth then putting a lighter to the inside briefly to see if the brief smoke smells similar.
To be so consistently on the right it has to be hot-exhaust related, and very localized around that exhaust. Burning muffler would only really come out the tailpipe to the back, not the right side.
Aside from rubber exhaust hanger cooking mildly from the inside out, only other possibility would be something very near the tailpipe where it snakes above the rear axle close to things... but again there I think heat is transferred faster via metal to metal or metal to rubber directly than through air. So I think it's something actually touching the exhaust.
Burning grease is possible, but seems like it would be more occasional, as grease doesn't really constantly fly out, and by accounts the smell is instantly reproducible on any hard driving.
My guess is the rubber hangers are of a soft quiet type for nvh, and can't handle the temps of high load driving and get a little hot (but don't reallt burn much), and the only reason we knoe is because our trucks have that tailgate window.
I drove over a dead skunk on the way home last night. When I parked in the driveway and walked around the truck I couldn't smell the burned rubber aroma that's normally there.
I can't wait for the burned rubber smell to come back. After 2 years I sort of miss it.
I drove over a dead skunk on the way home last night. When I parked in the driveway and walked around the truck I couldn't smell the burned rubber aroma that's normally there.
I can't wait for the burned rubber smell to come back. After 2 years I sort of miss it.