RAV4 smells like burning rubber after driving for half an hour (or a little more)

I have a 2003 rav4 with about 100000 miles on it. Over the last 4 months I have noticed that, whenever I drive half hour or longer on the highway the car starts to smell like burning rubber or burning antifreeze or something like that. I live close to work, play, and groceries, so I don’t drive it that long very often. I have not noticed decreased levels of any of my fluids. No change in performance either. I’ve had the oil changed regularly and no problems there. Any ideas? I am about to drive it a thousand plus miles and would love to get this figured out before I go. Thanks everyone!

I think you have a valve cover gasket that is dripping a little oil on the exhaust manifold. I would have a dye put in the oil. After the car is warmed up, the mechanic can spot the leak using “black light” to either confirm it is the valve cover gasket or another leak.

I think @Triedaq is spot on. A valve cover gasket leak is the most likely cause. And 100K is about when they start to leak. At least that’s the point my Corolla sprang a valve cover gasket leak. I just popped down to the auto parts store and ordered up a new gasket set. $40 maybe less. Took me maybe 30 minutes to install it, and no leaks since.

Well, there was the issue that the staff guy gave me the wrong gasket (technically, it was the right gasket, but for the wrong engine) and I had to walk 2 miles back to the auto parts store to get the right one, but that’s just part of being a DIY’er. I’ve since changed auto parts suppliers.

It doesn’t take much oil on the exhaust manifold to stink things up, and oil on the exhaust manifold does sort of smell like burning rubber. Coolant getting on something hot has an odor too, but more like an overcooked sweet pancake syrup.

Don’t try to fix this by tightening the valve cover bolts. Unless you have the factory service manual torque recommendations, and a calibrated torque wrench. It’s a common thing for DIY’er to overtighten those bolts to fix a valve cover leak, bend the valve cover sealing surface, and end up with a much worse (and expensive) problem than they had in the first place.

It could be something else, like a misaligned pulley or something, but I’d suspect the valve cover leak as being the most likely. Best of luck.

If it is the valve cover gasket, you might be able to see wisps of smoke if you get the right lighting, maybe with a flashlight at various angles. It’s worth trying to take a closer look when the engine is hot.

since it started about 4 months ago and it only does it on long trips,check the routing of all your hoses,one of the plastic retaining clips may have broken and the hose is touching something hot.
shorter trips probably don`t get the hose hot enough for a long enough period of time to cause it to start stinking,but longer trips would.
I think a leaking valve cover gasket would cause it to stink all the time,because oil would be leaking all the time, long and short trips.

If you’re about to take a +1000 mile trip, why not bring it in and have a pre-trip inspection performed?

Whatever is causing the smell, I’m sure will be found.


Thanks everyone! I am going to bring it in or an inspection before I go, and just wanted some ideas on what it could be before I go in. My mechanic retired and so I am going to have to go to a new one which brings up trust issues. First time posting on this site and I am grateful for the help.

By the way, oil smells acrid like burning rubber and anti freeze has a sweet smell.