“Let’s burn some rubber” feels like something Dom Toretto would smirk, the camera cutting to a dramatic shift into first, a leaden boot collapsing onto the throttle pedal as he wheelspins away with a cheeky wink.
“Wow, he’s so cool,” you’d think.
You’d be absolutely right, of course.
But real life isn’t quite so exciting, unfortunately. Burning rubber, unless you’re a professional drifter, isn’t good, and when you suddenly smell that slightly pungent taste drifting through the air inside your car, it almost always spells trouble. And, when we’re talking about cars, trouble equals dollars.
In this article, we’ll go through some possible causes of the burning rubber scent that you may be smelling in your car. Hopefully, one of these might ring true with you, and you may be able to start work on fixing it.
If you still don’t know what’s wrong – or you know but have no way of fixing it – we would always recommend taking your car to a professional mechanic. Using a ramp and sophisticated jacks is the most likely way for your car to be diagnosed correctly and therefore, fixed.
For now, though, let’s explore a few of the possible causes.
What Could Be Burning?
Let’s go ultra-basic here. If you can smell burning rubber, the likelihood is that something made of rubber is getting too hot in your car. Rubber isn’t used in too many places throughout your car, so that helps us narrow it down quite a lot.
Where do we find rubber in a car? Here is a list of some of the components that are made of this highly-useful material:
- Tires – As the contact point of the wheels with the road, tires are made of rubber to provide as much grip as possible, combined with minimal amounts of friction and drag. They also provide a far more comfortable ride than some other materials might.
- Hoses – In the engine, there are a few rubber hoses that are extremely important to engine performance. An example of one of these is the intake hose.
- Seals and bearings – There are many seals and bearings made of rubber in your car. One of the most notable causes of the burning smell could be the rubber seals in your AC compressor.
- Drive belt – The drive belt (technically called the auxiliary drive belt) is the belt you can see attached to several pulleys when you open the hood of your car. This belt is often made from rubber.
It’s also possible that the smell of burning rubber could be caused by something else that’s not made of rubber, but is nevertheless producing a similar smell. These could include:
- Garbage – The smell of old junk could simulate a burning oil smell.
- Oil – There could be an external or internal oil leak. Like rubber, burning oil can produce a bitter smell, so you could be smelling that.
- Coolant – Overheating coolant is also known to smell like burning rubber.
- Electrical fault – Examples of these kinds of things could be a blown fuse, or a lamp has gone out.
- Clutch – The smell of an overheated clutch is quite distinct, but if you’ve never smelt it before, you might mistake it for burning rubber.
Methods of Diagnosing the Fault
Let’s go through these different possibilities, one by one, exploring different ways to eliminate them from the possibilities.
1. Tires – This is one of the most obvious causes of burning rubber. This might especially be the case if you often slam your foot onto the throttle instead of gently squeezing it. It’s also likely to be a problem if you have a powerful engine, especially combined with skinny tires. They are more likely to spin up than not in this situation.
You’ll be able to hear the squeals of protest from the tires as you pull away – the screech is unmistakable. If you can smell burning rubber at this time, it’s probably down to this. If you think this could be the cause, jack up the wheels of the car one at a time (making sure to do so safely) and roll the wheel round in your hand, inspecting the tire for damage. If you see any smooth (or almost smooth) areas or any metal wires underneath the rubber, you need to get some new tires.
2. Hoses – Let’s take the intake hose, for example. Rubber becomes more brittle with age, making it more likely that it won’t be as effective as it gets older (like everything). The job of the intake hose is to take air sucked in from the atmosphere through a filter (creatively named an “air filter”) and then into the top of the engine, where it’s mixed with fuel and pushed into the engine to be burnt.
If the hose has leaks in it or has come loose, it’s possible that not enough air is getting to the engine. This would lead to a rich fuel mixture (a low air: fuel ratio), which means the engine becomes hotter. This heat could affect the intake hose and lead to that burning rubber smell. If this is the cause, you’ll probably be able to smell this burning rubber smell more intently as you’re driving, especially under hard acceleration or maintained high speeds. To fix it, you simply need to install a new intake hose.
3. Seals and bearings – Like all air conditioning contraptions, your air conditioning in your car uses refrigerant. This refrigerant goes through many pipes and other things to lead to the process of removing heat and moisture from the air. As well as being used to cool the air, the refrigerant is also used for lubricating the rubber seals. In most cars, the air conditioning is driven by a compressor attached to the drive belt.
This compressor contains rubber seals, lubricated by the refrigerant. Two possible things may cause a smell of burning rubber here. If you haven’t used your air conditioning for a long time (for example, through winter), the rubber seals will not have been lubricated and may have become brittle. Thus, they will not do their job as well, and the area may become hotter, creating the smell.
The more likely possibility is that you may have developed a refrigerant leak somewhere in the AC system. This would lead to the area around the compressor becoming too hot, which would also cause the smell. If you suspect the air conditioning system to be the culprit for the smell, turn off the air conditioning to see if the smell persists. If it does, you’ll need to take it to an automotive air conditioning specialist to get it fixed.
4. Drive belt – The auxiliary drive belt is often made of rubber. Over time, the drive belt can begin to become brittle and less effective at gripping the pulleys. Alternatively, one of the pulleys might become stiff or stop turning altogether. This would cause friction on the drive belt. Friction, as we know, manifests itself as heat – and there comes along the smell of burning rubber. If the drive belt is at fault, you will smell this smell for your whole drive.
Open the hood and look at the belt while it’s running. If one of the pulleys isn’t spinning, this could be the cause. Turn the engine off and examine the belt while it’s stationary. If you can see any noticeable cracks or wear, this could also be the cause. It’s relatively easy to change drive belts, and pulleys shouldn’t be too difficult, but if you’re unfamiliar with this territory, you may want to take it to a professional.
As we mentioned, there are a couple of other possibilities. These don’t actually involve oil at all but could create a similar smell.
1. Garbage – Old garbage, especially in hot weather, makes a nasty smell that’s possible to mistake for burning rubber. To see if this is the case, give your car a good deep clean and see if the smell gets a bit less with time.
2. Oil – Old oil can produce a smell somewhat similar to burning rubber in some circumstances. If you have an oil leak, it could be either external or internal. If there’s an internal oil leak, you’ll notice the smoke coming out of your exhaust as having a blue-ish tinge. If that’s happening, unfortunately, that means big trouble, and an engine rebuild might be in order. That’s a pricey one.
If there’s an external leak, this shouldn’t be so bad – park your car and leave it running for a bit. If there’s an oil leak, a puddle of oil will develop under the engine. It might just need a new seal or gasket, or potentially a new line or sump. Although these may be pricey repairs, they aren’t as expensive as an engine rebuild. It’s also possible that oil might leak from somewhere and then drip onto a rubber hose.
3. Coolant – If coolant is getting too hot, it can smell like burning rubber. The most likely causes of this are either a coolant leak or a damaged radiator, although a low oil level could also be a factor. Unless the fault is obvious, you’ll probably need to take your car to a garage to get it diagnosed and fixed
4. Electrical fault – When a fuse blows, it can cause a brief smell similar to burning oil. If this has happened, the smell will probably briefly come and then go just as quickly. It’s best to stop the car and check the fuse box and any other obvious electrical wiring if this happens. If a fuse has gone, make sure you know what circuit has tripped it and don’t use that circuit again. Getting a fuse replaced is a reasonably simple task.
5. Clutch – The clutch smells awful. It’s not very similar to burning rubber, but if you’ve never smelt it before, it’s possible to mistake it for burning rubber. To fix this, make sure you never rest your foot on the clutch pedal when driving, and only engage the clutch for the minimum amount of time necessary. If you can smell this smell, stop the car and let it cool for a couple of hours. When you start the car up again, the smell should be gone.
There are many possible causes of the smell of burning rubber. If you aren’t sure what it is or aren’t sure how to fix it yourself, drop it off at your local garage. Better safe than sorry.