Taking care of your car on daily basis is the best thing you can do. Although conventional routine service is designed to keep your Toyota Sienna running smoothly over time, some unexpected breakdowns can add heavily to your annual motor vehicle budget. Today we’re going to look at your sense of smell, and the clues it can give you about a possible malfunction, that’s why our team has made this content to help you in case you notice a burnt plastic smell originating from your Toyota Sienna . To help you check that it is nothing significant, first we will outline the different things that can produce a burnt plastic smell on your motor vehicle, then, in a second step, how to discover the source of this burnt plastic smell on your Toyota Sienna? .


The different possible sources and risks of smell of burnt plastic on a Toyota Sienna

So we begin our content page with the different possible sources of burnt plastic smell on a Toyota Sienna . Generally speaking, noticing a plastic or rubber smell is hardly ever a good signal. Obviously, modern cars are full of it and it could be the sign of a significant malfunction. Below we will review the different possible origins of burnt plastic smell:

  • Transmission oil: This is the most important possible origin of such an odor. Obviously, the action of gear or transmission oil is to lubricate the different elements of your gearbox so that all the gears and pinions are not broken, it also has a second action as a temperature regulator. However, in the long run, the oil will lose its performance and will not lubricate the parts and regulate the temperature as well, which will trigger the oil to overheat and thus give off that burnt plastic smell on your Toyota Sienna. You risk pre-wearing your gearbox if you don’t take care of it.
  • The accessory belt: Although rarer, it is possible with wear and tear that your belt, which is specifically made of rubber, will degrade and no longer rotate totally on its axis. With the friction that this will trigger the plastic will heat up and burn out, this reaction will produce a strong smell of burnt plastic or rubber in the engine unit block of your Toyota Sienna.
  • Defective hose wear: This case happens especially on Toyota Sienna that are starting to get a few years old or that have stayed a long time without rolling. In reality, storing your vehicle contrary to what you might believe will trigger the plastic parts to wear out more quickly. Hoses are the first to be suffering from this phenomenon. The rubber will disintegrate little by little and with the rise in heat of the fluid that circulates in it, it might melt. The risk of this problem is the breakage of the accessory belt.
  • A body component: Less general, especially present on Toyota Sienna’s that have suffered a small shock. Following a front or rear impact, wheel arches, bumpers or other plastic body parts that might have been bent might rub against one of your wheels and give off that burnt plastic smell. This may also pre-wear out your tyres.

How to find out where the smell of burning plastic originates from on a Toyota Sienna?

And now, to finish our content, we’re going to try to help you discover the origin of the smell of burnt plastic on your Toyota Sienna . Now that you know the different possible origins of this smell, we’ll just have to do some checks to eliminate the tracks that don’t concern you and resolve your issue quickly. If your Toyota Sienna smells hot, don’t think twice to go through our content on this topic.

  • Transmission oil: Nothing could be simpler, open your transmission oil cap (when cold) and check that your oil is reddish in colour and fluid enough. If you find out debris inside, and it is darker, it’s time to change it. Do not think twice to seek advice from our content to find out how to change the gearbox oil on a Toyota Sienna.
  • Accessory Belt: Visually check that your accessory belt is not in poor condition, it might also produce a whistling sound if it is in poor condition. Do not think twice to change it.
  • Hoses: For hoses, you will need to visually check all your hoses to find out if any are frayed or melted. If this is the case, change them.
  • Body parts: Last but not least, the last element that can trigger the smell of plastic or burnt rubber on your Toyota Sienna, a body component, check all wheel arches, that no component rubs against

    Whenever you have any additional questions about the Toyota Sienna, do not hesitate to consult our Toyota Sienna category.