Car Blowing White Smoke but Not Overheating? Find out Why

White smoke coming out from your vehicle is comparatively easy to ignore. For instance, your vehicle can blow white smoke when it is extremely cold. You may not take it as seriously as you would black smoke.

However, if white smoke keeps coming out of your car, your vehicle might need some help. You may think of some worst scenarios, like car overheating. But this cannot be the case all the time. Many other things can lead to your car blowing white smoke but not overheating simultaneously.

In this article, we will be explaining what can be the significant causes behind your car blowing white smoke but not overheating. We will be talking in detail about what white smoke blowing from a specific part of the car can mean. So, without further ado, let’s dig into the topic.

Where Does The Smoke Come From And Why?

Smoke from the exhaust system or other engine components can vary. Even though white smoke coming from cars is perfectly normal, black smoke often indicates fuel-related problems.

White smoke can still signal other underlying problems in your car or other engine components that you need to work on immediately before the actual fire breaks out.

So, the next time you see your car blowing white smoke but not overheating, look for the root cause. You have to determine the exact location from which this white smoke is coming and proceed with the solution.

Now let’s look at the 4 main engine components where white smoke can come from in a vehicle.

Car Blowing White Smoke From Exhaust System

Your exhaust system is the first place from where you notice white smoke coming out. There are five main reasons why your exhaust system might be blowing white smoke:

Cracked Cylinder Head Gasket and Coolant leaking

A failed head gasket is the common reason why you see your car tailpipe giving out white smoke. To check if the white smoke blowing out of the exhaust pipe is due to a cracked cylinder or blown head gasket and coolant leak, run a little test. Here you have to check if the white smoke is still coming out when the engine is warmed or even accelerated. Suppose at this stage the smoke coming out of the exhaust pipe is white and has a sweet odor smell then your coolant tank is leaking coolant and is eventually getting burned along with fuel.

The main culprit behind the coolant leaking is a cracked cylinder head gasket. No matter how slight the damage is, the coolant can still find a way to leak out of the cylinder head gasket into the combustion chamber, combine with engine oil, and spoil it.

At first, this problem might seem trivial to you. However, if not treated on time, the coolant level can get pretty low, and as a result, the engine will overheat. In the long run, this can actually result in a head gasket failure.

The intake manifold gasket is another place where coolant might leak. A leaky intake manifold gasket may cause symptoms that are remarkably similar to those of a failed head gasket, faulty entire engine block, or cracked cylinder heads if your car has water jackets that pass via the intake manifold.

Poor intake manifold gaskets are frequently less expensive and simpler to repair than a failed head gasket. Make sure you conduct some tests and diagnostics to identify the precise failed head gasket that is leaking if you observe white smoke from the exhaust. When you avoid paying a hefty repair bill for a vehicle, the expense of an inspection and diagnostics fee will pay itself.

The best way to determine whether your car has a failed head gasket or not is to run a leak-down test. A leak-down test will confirm the failure of the leaking coolant and the fuel.

Some people have succeeded with head gasket sealers to stop leaks, but this is not a thorough and long-lasting solution.

Condensation

Condensation is another common cause of white smoke coming out from the exhaust system. The main reason behind this phenomenon is that when the weather gets cold and you start your car, the hot gas from the exhaust system meets the cold air outside. As a result, you end up with condensation combined with steam. This white exhaust smoke would come in small intervals and usually clears up after 30 seconds.

Fault in the Fuel Injector

White smoke may also come out from the exhaust system due to a fault in any fuel injectors.

The job of a fuel injector is to inject fuel inside the internal combustion chamber at an appropriate time. As a result, when the combustion chamber is left open or has a major leak, it will dispense too much fuel. Since the combustion chamber can’t burn too much fuel at once, the leftover fuel is released as a cloud of white smoke.

You don’t have to worry as this problem has a straightforward and affordable solution. All you need to do is replace the defective fuel injector or its o-ring with a new one. Because it is technically challenging to determine which fuel injectors might be faulty, it is better to replace all of them at once as they are inexpensive.

Water in the Exhaust System

Your vehicle might also blow white smoke from the engine bay when its turbos are damaged due to water leaks. What happens here is there is a massive leakage from dirty or damaged turbos into the cooling channels. This affects the engine’s performance, so it is too late to fix it. The only cure here is to replace the turbo to stop the water from leaking out of it and producing white smoke.

Cracked Engine Block

You might end up with a cracked engine block in the worst-case scenario. It will probably cost the most money to fix this issue. Moreover, you cannot be sure here what is the actual cause behind the white smoke coming out of your vehicle. Here, you will have to get professional help from a mechanic.

In the worst situation, your engine block may be completely cracked. This issue will probably cost the most to fix. Additionally, until you have a mechanic analyze your car, you won’t be able to determine which of the aforementioned issues is the real reason for the production of white smoke.

White Smoke Coming From Engine

White smoke can also come from the engine, which would have a completely different meaning. Two of the most common causes behind white smoke coming out of the engine are engine oil leaking and an error in the engine control module. Here, we will be discussing both of these problems in detail one by one.

ECM Error

Often due to some random computational ECM or engine control unit error, you might end up with your car blowing white smoke. You must fix or reprogram the engine control unit to correct the error of the fuel pump injector timings in the engine control unit.

The Engine Control Module might send down faulty signals to the fuel injectors, which will cause irregular fuel discharge. In short, whenever your car’s engine receives more or less fuel, it will start to blow out white smoke.

You don’t have to worry if you notice white smoke coming out of your car due to EMC. A simple solution here is to reset the ECM or have it reprogrammed. You can usually do this by unplugging your car battery for a while or having it reprogrammed by mechanics or experts.

Engine Oil Leakage

The oil is burning inside your car if your engine blows white smoke. This thick white smoke, most of the time, smells of tar or asphalt and has a blue hue. The likelihood is that oil is leaking from somewhere and that it spills onto the catalytic converter or exhaust manifold before burning off.

Additionally, oil can enter the fuel system and burn when the engine is operating. Make sure to have a checkup for your car oil system regularly. A leak-down test is mandatory once a month at least to be aware of any potential leaks in your car engine.

Check Out How to Fix a Car That Smokes Under the Hood:

White Smoke Coming From Radiator Cap

Older automobiles are more likely to experience radiator or oil filler cap white smoke. The three reasons your car radiator is going to blow white smoke are:

Residue Build Up

The first and foremost reason behind your radiator or filler cap blowing white smoke is the residual build-up. The engine can sometimes get hot due to residual build-up on the cap. Eventually, as the engine gets hot, oil burning there will produce white smoke. Fixing this at the right time is essential and can land you worse consequences, like the engine blowing up.

Worn Piston Rings

Your radiator’s piston rings must tuck oil into the cylinder properly. However, if you ever end up with worn piston rings or cylinder head gaskets, the oil leak would be huge. As a result, oil that enters there will burn before shooting past the piston rings.

Clogged PVC Valve Seals

Clogged or broken PCV valves or tubes are another cause of the smoke. If the crankcase ventilation valve cannot suck the smoke back into the engine, it is re-burned, and the smoke will rise through the oil filler cap. The air intake here is out of the track, causing not enough air concentration into the fuel.

You would undoubtedly want to stop the oil leak as soon as possible. If the oil is not lubricating the engine parts, they will become worn out and damaged. That will inevitably cause many other issues, many of which can be very expensive to resolve. We’re confident that is not something you want to go through.

FAQs

Final Considerations

Next time your car blows white smoke for a long time, take it seriously. If you aren’t sure where to go, rely on getting roadside assistance to help. Because if you don’t take proper care of your car engine, you might spend a hefty cost. It is always better to fix smaller engine components than the whole engine.