[Fixed] Smoke Coming Out of Car Vents! Causes & Fixes! 

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Are you driving on the road and suddenly see smoke from your car vent? Nothing can be more frustrating than this, especially when you don’t know what is causing this smoke. But don’t fret; we are here to figure out the reason for you and will ensure to provide you with the best possible fixes. 

There could be numerous reasons for you to see smoke coming out of car vents. Some of the reasons include car overheating, coolant leaks, oil leaks, damaged oil filler caps, clogged drain holes, some electric problems, and high humidity in the vent, among others. 

We have compiled a detailed guide for you explaining some of the main reasons for smoke coming out of car vents. We will also provide you with some simple fixes you can try to solve this problem. So, keep reading if you don’t want to miss out on this opportunity. 


Why Does Smoke Come Out of Car Vents? 

If this is your first time seeing smoke coming out of the car vents and you are wondering what could be the reason behind this, here is a list of some of the frequent situations that could lead to this problem. 

  • Car Overheating 

The first and foremost cause of smoke coming out of the car vents is overheating problem. If you have been driving nonstop for the past few hours, your car’s engine and other machinery might have heated up. 

Owing to their heating up and the quantity of water decreasing in the car, you could eventually see smoke coming out of the vents. 

  • Overuse of Heater 

Another obvious cause of the smoke coming out of your car vents is the overuse of heaters. If you use the heater in your car too often, this might have caused the leakage of the core. Whenever the core is leaked, smoke is produced, which can sometimes come out of the vents. 

If you notice no odorr in the smoke and more than smoke, it’s icy fog; this is a clear indication of a low coolant level. 

  • Low Oil Level 

If you use the air conditioner regularly in your car and haven’t paid heed to the oil level in the car lately, this can also result in the production of smoke. Though there are some other factors too that affect the oil levels in your car, frequent use of air conditioning is the most common one. 

So, check the oil level in the car to ensure that this is not the reason behind the smoke. 

Here is a quick YouTube tutorial for you to learn how to check the oil level in your car. 

  • Clogged Drain Hole 

With air conditioners, whether they are used at home or in your car, one deniable phenomenon is condensation. Usually, these air conditioners come with built-in mechanisms to collect the condensed material and later on change it into vapors for cooling down the cars. 

However, older car models feature a drain hole used by the condensed water to escape. If the drain hole in your car is clogged and you haven’t gotten it cleaned for a long time, the condensed water will begin accumulating within the air conditioner and finally escape as smoke from the car vents. 

  • Worn Out Car Components 

Another reason smoke might come out of the car vents is some worn-out car components. If you haven’t taken your vehicle out for maintenance for a long time, one of its internal components might start acting up, resulting in the appearance of smoke from its vents. 

Due to the damaged internal component, your car’s internal machinery might overheat, which, as discussed above, can lead to the production of smoke. In this case, you can even notice a burning smell in your car. 

  • An issue with the Compressor Clutch 

Some problems with the compressed clutch of your car can also result in the car’s internal machinery getting all heated up, eventually producing smoke from the car vents. 

  • High Humidity

If the humidity in the surroundings around the air conditioning unit in your vehicle are a lot lesser than the humidity in other parts of the car, you will, in no time, see fog coming out of your car’s AC vents. What helps you differentiate fog from smoke is the burning smell of smoke. Fog, on the other hand, can give you chills as it is icy cold. 

  • Damaged Oil Filler Cap 

If the oil filler cap in your car is damaged, this could cause the fuel to escape from the tank. As a result of this, the car engine will burn the fuel, eventually resulting in the production of smoke. If not taken care of immediately, this problem can cause disastrous results. 

  • Oil Leakage 

If you haven’t closed the oil tank properly while filling it up in the last gas station or the oil tank has a tiny hole in it, resulting in oil leakage, you can experience smoke coming out from the car vents. Smoke releasing, in this case, will have a foul smell. 


Fixing Smoke Coming Out of Car Vents 

Now that you have looked at all the possible reasons for smoke coming out of your car vents, it’s high time to take you toward the fixes of this issue. 

  • Draining Water from Heater Box 

The first fix you can try to stop the smoke from coming out of your car vents is to drain water from the heater box. As we have mentioned above, a clogged drain hole is one of the major causes of smoke coming out of vents, so removing water from the heater box manually can help you resolve this problem. 

Locate the HVAC box drain pipe in your car. Once you get sure that the water accumulated in the drain hole is causing the appearance of smoke, use a pump to pump out the water from the clogged pipe. You can also do so by removing the bent in pipe, i.e., unclogging it for the same. 

  • Cleaning the Air Filters 

If the smoke is coming out of the car vents because of humidity around the AC vents, all you have to do is to clean the air filters. Cleaning the filters, in this case, will help match the humidity level of space around the vent with the humidity level in the rest of the car. 

Check out this YouTube tutorial if you haven’t cleaned your car’s air filters before. 

This can also be done by running a high-power fan inside your car. Adjusting the temperature of the AC inverter in your vehicle and moving it to the hot temperature for a while can also help you stop the smoke coming out of the car vents. 

  • Check the Electric Connections 

Another fix you can try to solve this issue is checking your car’s different electric cable connections. Rusted or loose battery cables could be the leading cause of the smoke coming out of the vent issue. 

So, ensure to inspect all the cable connections and tighten all the loose cables. In this case, you can also change the damaged or broken cables for a quick fix. 

  • Replace the Heater Core or Check for Leaks 

Leakage of the heater core is also a leading cause of smoke from the car vents. What’s best to do in this case is to replace your older heater core with a new one. However, if you don’t have the budget for a new core, you can take it to a professional, check it, and fix the leakage. 

  • Getting a New Compressor Clutch 

If the smoke is coming out of your car vents because of a damaged or problematic compressor clutch, you will have no option but to replace it with a new clutch. Unfortunately, repairing the clutch isn’t an option for you as it is a difficult process and will cost a lot of money. 

  • Fixing the Car Component 

Another fix you can try for this is to get the component of your car fixed. As we have mentioned earlier, any problematic car component can lead to the appearance of smoke from the car vents. So, the best solution for you is to take your car to a professional so the component causing the issue can be located and fixed. 

  • Changing the Oil 

If you have been driving your car for a long time, you must have heard others mentioning the term oil change. This might not seem too important, but it is pretty crucial for the efficient working of your car. So, if you haven’t changed your car’s oil for a long time, get it done immediately.  


What Are Different Types of Smoke that Comes Out of Car Vents? 

When it comes to smoke you might see coming out of your car vents, no single kind of smoke comes in all situations. Actually, the smoke’s color, smell, and impact greatly vary depending on your car’s condition and the reason behind this smoke. 

Here is a list of all the kinds of car smokes you must be aware of. 

  • White Smoke 

The first kind of smoke you usually see coming from your car vents is white smoke. Unlike the smoke produced as a result of electrical problems with some car components, this one is odorless and is hard to detect in the beginning. But as time passes, it starts filling up the car space and becomes noticeable. 

  • Black Smoke 

This is one of the most harmful car smoke and clearly indicates that something is burning inside the car machinery. Also, it comes packed with a lot of toxicity, so you must immediately act after noticing black smoke from your car vents. 

  • Grey Smoke 

Unlike white smoke, it isn’t hard to notice and is not too toxic like the black smoke we mentioned earlier. 

  • Blue Smoke 

If you see blue smoke coming from your car vents, it is a clear signal of an oil leakage seeping into the hot part of your car’s engine. This issue needs immediate action. 



Is It Safe to Drive With Smoke Coming from Car Vents? 

No, driving while you see smoke coming out of your car vents is strongly not recommended. Regardless of the color of the smoke you are seeing, it’s best to pull out and figure out the problem before moving your car any further. 

This smoke can come with huge health hazards and be lethal for you too. So, if you don’t want to burn your car to ashes, it’s best not to drive with smoke from your vents. 

How Much Does it Cost to Get the Smoke Coming from the AC Vents Fixed? 

It greatly depends on the type of smoke you see and its source. For instance, if the smoke is white or grey, i.e., it is not because of some serious issue with your vehicle, you can even get it fixed for free. 

However, if serious damage to your car or an electrical issue is causing the smoke from the car vents, it can cost you around $600 to $1000 to get rid of it. 

Conclusion – [Fixed] Smoke Coming Out of Car Vents! 

In this guide, we have taken you to all the possible reasons for the smoke coming out of your car vents, along with pinpointing the components that might be involved in this problem. We have also provided you with a long list of fixes you can try to get rid of this issue. 

Hopefully, one of these fixes will help you prevent the smoke from coming out of your car vents, and you won’t feel pressured to see smoke from the car vents in the future. Happy driving! 


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