Burning oil smells are always intimidating. And you might have noticed this irritating smell just after switching on the heater. What would you do?
Why the car smells like burning oil when heater is on? The most possible reasons are:
- The heater hasn’t been serviced for more than a year
- Overheating issues
- A dusty and filthy furnace filters
- Over-heated motor
- A dysfunctional oil filter
- A damaged furnace, etc.
Here, we explained the detailed reasons why the car smells like burning oil when the heater is on and what would you do. Read on and check this out.
What to Do If Your Car Smells Like Burning Oil when Heater is On
Before delving into the specifics of the root causes, let’s take a look at the possible solutions.
| Reasons | Solutions |
| Heater Activated After a Long Time | Keep the heater on for at least half an hour while leaving the doors open |
| Delay in Heater Servicing | Go for servicing immediately |
| Old or Filthy Furnace Filter | Install a new one or clean the old filter |
| Bad Heater Motor | Consult a HAVC expert |
| Dysfunctional Oil Filter | Go for servicing |
| Blocked Vent | Clean with dry cloth or duster |
Why Does Your Car Smell Like Burning Oil When Heater Is On?
In this section, you will observe the terms “dirt,” “dust,” “debris,” etc. All these always become mixed with oil (greases, lubricants, service oils, or fuel), as lubricants are essential for a car’s function.
When we say dirt burn, we mean that the dirt is mixed with oil and burned. Now, through our expert observation, we’ve identified the following reasons why cars smell like burning oil when the heater is on.
Heater Activated After a Long Time
Surely, you have not switched on the car’s heater during the whole summer. When you first encounter icy weather after a long period and turn on the heater, you may notice an oil burn smell spreading inside the car.
The cause is simple: the unused heater retains some dusty particles, which burn off after switching on, creating an oily odor.
Solution
It is not a very worrying context. You have to keep the heater on for at least half an hour while leaving the doors open. There will be no smell once all of the dust has been burned. But after this treatment, if the smell remains, you must contact an expert immediately.
Delay in Heater Servicing
As per standard, your car’s heater must be inspected and serviced once a year. If you are experiencing an oil burn odor while the heater is running, there is certainly a mechanical fault.
This fault makes the heater overheat and causes slow burning of adjacent pipes, cords, tiny parts, etc. Thus, the summation results in creating an oil-burn smell.
Solution
Check your car’s service book. When did you check the heater’s fitness? If the period exceeds a year, it is crucial to visit an auto repair shop as soon as possible.
Old or Filthy Furnace Filter
Just like your home’s air cooler filter, a car heater’s furnace filter also requires replacement and regular maintenance. Any negligence triggers the burning oil smell from the heater. The furnace filter has a lifetime; it should be replaced every 12,000 to 15,000 miles.
In association with the filter replacement requirement, it should be cleaned as frequently as possible, depending on your heater’s workload. If you reside in a cold area where winter is dominant, you must clean the filter more frequently than in the warm season.
Solution
Calculate the mileage after the installation of a new filter. If your car has run more than 12,000–15,000 miles, it is time to replace the old filter with a new one. However, if the mileage is below the mentioned figure, take it out and remove the dirt.
Bad Heater Motor
Heater motor can behave badly due to inadequate ventilation. The ventilation issue is usually generated by ripped-off ductwork, blocked filters, faulty coolant, etc.
In this case, the motor exceeds its capacity and generates excessive heat. And this overheated body burns service oil, dust, small parts, etc., generating the oil burn odor.
Solution
Consider it a serious issue, check the ventilation-related issues, and solve those to bring back standard working conditions for the motor. Please remember, a bad heater motor can blow up the whole heater and the surrounding parts.
Dysfunctional Oil Filter
Similar to a furnace filter, a long-gone oil filter can also generate a burning oil smell. It forces the heater towards unnecessary heavy duty. Thus, it creates overheating conditions resulting in burning debris and leaking oil. And this produces an oil-burn smell.
Solution
To resolve this issue, a timely replacement of the oil filter is always better. If the issue occurs just after a few days, cleaning is essential.
Blocked Vent
An unused heater’s vent usually contains dust and debris. When turned on, the generated heat causes those to burn, emitting an oil-burn odor. It is a common issue if you reside in an area where winter lasts only for 2-3 months.
Solution
The solution is simple: just clear the vents with a dry cloth or duster.
How to Prevent This Issue’s Occurrence?
It is well said that prevention is always better than cure. So, what can you do to prevent the issue?
- During winter, activate your heater for half an hour weekly
- In every 6 months, check the fitness of the heater, heater motor, filters, piping, and other associated parts
- If you live in an area where winter lasts six months or more, go to an HVAC expert every two months
- If you detect an oil burn smell after switching on the heater, take care of it right away. Any delay will cost you more, even a major breakdown in the car
Bonus: If you’re still coinciding on the matter, here’s a cool video on how you may fix this issue with your car!
FAQs
We have discussed some common queries people have in this section.
The very basic reasons are any sort of oil leakage, delay in oil change, low oil level, etc.
Yes, but it is better to identify and resolve the issue at the very beginning. If you are unable to do that now, address it as soon as possible.
Yes. Generating burning oil smell and smoke are common health issues associated with cars. Though these are common, they are not normal. You must take immediate action to resolve the issue.
Final Thoughts
Running a heater is essential in the winter. But if your car smells like burning oil when heater is on, resolving it early is beneficial for a smooth driving experience. So, a weekly self-checkup of heater filters, connections in and out to the heater, etc., is an effective and easy solution.
Still, we suggest you visit an auto repair shop once a month to maintain the top-notch condition of your car. It will not break your bank but will save you tons of money in the long run.