More often than not, a smoking engine can point to two major problems: a leak in the engine or too much friction caused by moving engine parts.
Either way, smoke is a sign that there’s a serious problem that needs to be addressed immediately. Otherwise, you run the risk of your engine overheating and getting damaged.
Because of this, it’s a good idea to familiarize yourself with the meaning of different smoke colors, the most common causes, and whether it’s possible to drive with a smoking engine.
Yes, smoke color matters because it can help you pinpoint what’s causing the issue.
Blue smoke is oil, white smoke/steam is coolant or water, and black smoke means the vehicle is running too rich.
The smell of the smoke can also be a good clue as to what is causing it. The place where the smoke is coming from is another clue. If it’s coming from the tailpipe, it’s the product of something that is happening inside the engine. If it’s coming from under the hood, well, that’s a different issue.
If the smoke is coming from the engine compartment, it will either be due to hot coolant coming from a hose and/or making contact with the exhaust manifold, or it will be some kind of oil or fluid that finds its way to that very hot part of the engine.
Smoke from under the hood can also be due to electrical issues or even fires that start.
Caution: If there is a lot of smoke escaping from the edges of the hood, be careful opening it because you may find a roaring flame in the engine compartment due to oil or fuel leaking onto the exhaust.
Typically, if there’s an oil leak in the engine, or if there is a transmission or power steering fluid leak making its way to the hot manifold, the smoke will be blue.
When any kind of oil leaks onto hot engine components, it makes blue smoke that smells like burning oil, and different types of oil will have different smells.
If there’s white smoke coming from the engine, there’s likely a coolant leak from a coolant hose, the radiator, or some plastic part of the cooling system that has split or cracked and allowed coolant to escape. When the coolant burns, it creates a sweet-smelling white smoke.
Keep an eye out for the problems that lead to smoking engines. Some of the most common causes include (but are not limited to) oil and coolant leaks, electrical problems, overheating engines, and burning contaminants.
When oil and coolant leak into the engine, they can burn and create smoke when they come in contact with hot components. The color and smell of the smoke depend on what’s burned. Address this problem as soon as possible to avoid losing too much motor oil or coolant.
When the wire harnesses burn, it’s usually due to a short circuit or an overheating of wires due to high electrical load such as the cooling fan. When connectors begin to oxidize they develop resistance, which leads to heat and the melting of connectors and wires near the connectors. Starters and alternators can overheat and smoke and even set fire to nearby components; and once the fire starts it causes a lot of damage.
Components such as gaskets and seals can burn, melt, and become misshapen because of an overheating engine.
Yes, if the issue didn’t render your vehicle inoperable, you can technically drive while the engine is smoking. However, that doesn’t mean you should, as you run the risk of further damaging your car.
Unless you’re confident you can drive to the nearest service center without destroying the engine, it’s best to pull over and stop driving as soon as you spot engine smoke. This minimizes the risk of your engine overheating and sustaining permanent, irreparable damage.
You can call roadside assistance or a towing service to bring your vehicle to the nearest mechanic and have them run diagnostics. There’s a good chance you’ll need to buy replacements for damaged or inoperative engine parts.
Even if you’ve somehow confirmed that the source of the smoke isn’t due to overheating, it’s a bad idea to drive a vehicle with a smoking engine.
Smoke is a clear indicator that something is burning in your engine, which means a component is likely damaged or even inoperative. It’s a good idea to have your vehicle inspected by a professional if smoke comes out of places it shouldn’t.
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.