White Smoke From Exhaust On Startup: How To Fix It

The hours of dread when you notice white smoke from exhaust on startup in your car is something that no car owner would want. Yet, this fuming issue has been the start of the repair and replacement stories of several engines and engine parts.

While white smoke from your car’s tailpipe can sometimes go completely unobserved. However, there are a few instances when you may want to pay attention to the real problem.

• When It’s An Issue
• Reasons For White Smoke
• How To Solve
• Diesel Engine vs. Gas Engine
• Low Oil Or Oil-change
• Different Colored Smokes

White Smoke From Exhaust On Startup: Knowing When It’s An Issue

Knowing what is normal and what needs attention is as important when diagnosing and fixing the engine problem.

While you may note that frail and disappearing smoke during colder months is normal, you may want to take things into your hands if you notice thick and heavy smoke on warmer days. It is also a problem when you observe other indicators of a failing engine part, such as burnt smell and diminishing engine power.

What Causes White Smoke From Exhaust On Startup?

Those fuming white smoke from your car’s exhaust sometimes becomes heavy and murky. When you start your car, these white smokes are no coincidence.

To understand how you can fix this problem, you’d want to know what causes such soupy white smoke to come out from your car’s exhaust on startup.

Here are a few possible explanations:

Condensation Buildup

Not every white smoke that you see when you start your car’s engine is calling for trouble. If you notice thin threads of white smoke on startup, which disappears shortly after it appears, you know its condensation build-up.

When you start the engine of your car, it heats up. The heat cause condensation and in willowy and disappearing white smoke, it’s a cause of concern when this smoke lasts longer than just a few minutes. If you notice that the white smoke is slithering out almost constantly, you might need to run a check.

It is also worth noting that this is a common scene in countries whether the weather is cold. If the place you live in is a hot and humid area or has warmer temperatures, thick white smoke is a sign of damage to your engine.

In such cases, your car may have internal issues.

Coolant Leak

What prevents your car’s engine from simply melting away the adjacent pipes when it heats up significantly? It is your car’s coolant system.

Not only does it protect the engine from overheating issues, but it also makes sure other parts like the head gasket are guarded against potential damage. You may know the coolant as antifreeze and as the name suggests, the built heat is transferred via the coolant. This is in addition to making sure the engine is maintained at an ideal and safe temperature.

Leaks, damages, and dysfunction of these glycol-based coolants have long been responsible for a car’s major engine failure. Likewise, white smoke at the startup of your car is one of the problems that occur when there is a leak or damage to the coolant.

Lucky for you, there are a few extra indicators, along with white smoke fuming from the exhaust to know whether the antifreeze is the real cause. If you notice that the reservoir of the coolant is running on low and the white smoke smells (with some pointers on how to get smoke smell out of car) somewhat sweet, you might have a coolant leak into the engine, and hence a heating issue.

If you notice all the three indicators of white smoke being caused by coolant damage, it is best to immediately fix the leakage. Otherwise, the leakage is capable of contaminating engine oil and hence causing further damage.

UTI suggests that the importance of a well-operating coolant should not be undermined and should be changed every 5,000 to 10,0000 miles depending on the car’s model.

Now, white smoke from exhaust on a startup linking to a coolant leak can be caused due to the following reasons.

Broken Cylinder Head

When dense white smoke is fuming out of your car’s exhaust when you start the vehicle for longer periods, overheating can be a major problem. Such an issue is correlated to the coolant’s failure or leakage, mostly caused by a broken cylinder head.

When the engine’s antifreeze system fails, there is rapid overheating. The overheating will eventually, more often than not, quickly cool down as well. This rise and fall in temperatures cause the cylinder head to expand and contract unpredictably.

This is particularly common in the cylinder head that is made of cast iron, aluminum, or a mixture of the two. It creates stress from overheating central to a crack in the cylinder head.

If the head is cracked or damaged, the possibility of the coolant liquid entering other cylinders or parts of the engine becomes inevitable. At times, if the leak occurs for a longer time, say overnight, it might even pass in the combustion chamber. This would, in turn, cause the coolant to completely burn off, releasing white smoke on startup.

Blown Head Gasket

What causes the most damage to your engine is when there is damage to your car’s internal combustion engine. This famously includes a blown head gasket, causing white smoke to come out of the car’s exhaust pipe.

This is primarily because there is no immediate warning indicator for the driver or the passengers to understand that there is damage in the car’s head gasket. It is not until you have driven several miles that you notice seething white smoke from your front hood.

As part of the internal combustion system of the car’s engine, a head gasket’s performance considerably determines your car’s engine performance as well. The integral function of a head gasket is to be a clocking seal for the cylinder’s firing pressure and between an engine block.

Further, it also stops any leaking oil from entering into other parts. In short, it is also responsible for managing the extreme pressure that is built.

A “blown” head gasket is a damaged or leaking head gasket. White smoke from the exhaust tailpipe is just one of the many signs of a head gasket in need of repair. Along with that, you may notice sudden coolant loss, bubbling reservoir tank, as well as, milky white color in oil.

In addition, you would notice your engine’s power system drop suggestively, and when that happens, you may want to contact a professional without losing any time.

Splintered Engine Block

As soon as you notice white smoke making its way out of your exhaust tailpipe, you know there is an internal issue with the engine. One other way a coolant leak can lead to dissipating white smoke on startup is a damaged engine block. Unlike other parts, a splintered engine block is challenging and expensive to replace.

Along with noticeable white smokes, there are other indicators through which you would be able to comprehend whether the engine block is overheating and damage.

If you check your coolant and notice that either, is it frozen or discolored, this is warning enough that your engine block might have been compromised. Other than that, you can see fluid under your car and a drip in the engine’s performance as well.

Fuel Injector Impairment

Fuel injectors have electronic controlled valves, using which fuel is injected into the car’s engine through a spraying technique. This is a problem that is particularly relevant to cars that run on diesel. If your diesel run vehicle is puffing out white smoke from the hood, you may want to ensure the condition of the fuel injector.

Both ignition timing and cylinder pressure must match for the right setting during the spray injection. Since the timing used to spray diesel into the cylinder plays a big role here, a disparity in the synchronization of this very timing can cause the injection to falter.

This video explains the function and importance of a fuel injector just impeccably.

In turn, there would be too much engine work in too short a time, leaving the fuel to be unburned during the startup. Consequently, you would see white smoke from exhaust on the very instant.

Valve Seal Leakage And Piston Ring Damage

Valve seals in a car’s engine are color-coded and can act as a lock and key for any opening and closing systems of the engine. Bad valve seals can be a major issue causing white smoke out of the exhaust.  These seals control oil and air mixture, pressure, and how much should be let into the combustion chambers.

When the valve seal has leakage or deteriorates when unchanged for a long time, you might notice a lot of white smoke with a blue-ish hue. After you start the engine, you may notice how the smoke rises quickly and remains for a longer period of time. Although it would disappear, white smoke caused by a damaged valve seal can be heavy.

Similarly, in your car’s internal combustion unit, there is a piston ring attached to the outer piston, working as another seal as well. Any leak or impairment in these rings can cause similar white smoke to fume out of the exhaust on startup.

Here is how you can check if your piston ring is functional or has wear-outs to be taken care of.

Transmission Fluid

Too much or too little transmission fluid inside your car’s engine can unsettle the proper functions of the rest of the combustion system.

This, in turn, can cause white smoke from exhaust on startup. Another sign of issues in transmission fluid along with white smoke is a burnt smell that you might notice after a while.

If your car engine intakes more fluid through the hose than it is required to, the oil or fluid will be completely burnt. That’s when you would be aware of a striking burning smell.

How To Solve White Smoke From Exhaust On Startup Issue

To every problem causing white smoke from exhaust on startup, there is a solution. Depending on what causes the fuming in the first place, few solutions are simply nut tightening and repair.

Still, some would require more time as well as cost. While you can fix a few issues by yourself, intricate ones would require professional repair hands.

Step 1: Checking Coolant Levels And Color

One of the root causes of a possible white smoke emission is related to the defective functions of the engine’s coolant system. That is precisely why car experts and manufacturers never stop singing about how important it is to have your coolant flushed and renewed now and then (as well as using a good coolant system cleaner).

With a little acquaintance with car engine parts, you’d be able to open the hood to figure out the exact problem. Always remember to let the engine cool down before you open the hood. Exercise some caution as you attempt to figure out if the coolant is on appropriate levels and never touch either the tank cap or the radiator cap.

Touching either of which could be potentially hazardous to you. You can use a stick to check if the coolant levels are too low. If so, you’d need to fill the reservoir up with more coolant fluid. A coolant flush (and figuring out how to flush coolant system) is suggested every once in 30, 000 miles for it ensures that there is no contamination, leaks, possible acidic antifreeze as well as rust.

Step 2: Checking The Manifold And Head Gasket

The inlet manifold is to your car, what your lungs are to your body. In short, the engine breathes through the intake manifold gasket.

Before running your mandatory check of the head gasket, the inlet manifold gasket needs to be checked for cracks and defacement. Since the intake is generally made of rubber, or in some cases plastic, you could expect deformation on it.

Replacing your inlet manifold gasket can cost you anywhere from $100 to $500, and to save up on that, this video explains how you can do it yourself.

Next, you may move on to check the head gasket. From overheating of the hood to white smoke from the exhaust, each sign is an indication that your head gasket seal may have been comprised. A crack or displacement in that case would be visible to the human eye.

Similar to engine blocks, replacing a head gasket would cost up to $2000 and still be cheaper than repair costs for the part.

Step 3: Inspect Cylinder Head And Engine Block

Likewise, you would want to run a good check on the cylinder head, whether is shut down completely and the engine blocks itself.

Cylinder heads are mostly made of aluminum and hence the rapid variation in temperatures can cause the cylinder to warp, and eventually crack. Depending on what the cylinder head is composed of, it can take up to $1000 to repair it, and up to $3500 to replace it.

The majority of the costs associated with replacing a cylinder head are the cost of the labor. If you have a luxury car and live in an area where labor cost is higher, this replacement is one expensive repair work.

Repairing an engine block crack can be done in the following ways: cold metal patch, crack welding, and stitching cold metal. Depending on the design of your car’s engine, repairing an engine block is a time-consuming process, which can cost you up to $5000.

You’d be surprised to know that replacing a smaller engine block can save you up to $1000 to $1500.

Step 4: Check Fuel Injector, Valve, And Piston Sing

Next, run a thorough check on the fuel injector. You might inspect whether it requires replacement, repair, or maintenance. In some cases, the injector opening becomes clogged and dirty and starts to show irregularities.

If the issue owns to carbon accumulation and clogs formation, you may want to clean up the gunk. However, if you notice that there is no clog or gunk deposit, you may want to replace the injector immediately.

Next, check the valves and piston rings. You may want to keep in mind that to check these small parts, a complete stripping of the engine is required. Due to this very reason, it is advised that you let a professional mechanic handle the disassembling, although it would be costly.

Among the three, replacing a piston ring can be expensive and lengthy.

White Smoke From Exhaust On Startup: Diesel Engine Vs. Gas Engine

Among the causes we mentioned that lead to leaking white smoke from exhaust as you start your car, each applies specifically to the type of engine your vehicle has. For diesel-run cars, the causes of this white smoke are different as they are for a gas-run car engine.

When you have a diesel-powered vehicle, the possibility that white smoke may come out of the hood would be due to coolant issues. Leaky coolant owing to damaged head gasket, engine block, or cylinder head is what may destabilize the fluid transmission. It would also be due to the fluid being transferred into the combustion chambers of the engine.

In the case of gas or petrol engines, injection and valve system failures play a major role in why there could be smoky fumes from the exhaust on startup. With possible overheating of the engine, condensation, and fuel pump failure you can expect to notice similar issues.

White Smoke From Exhaust On Startup: Low Oil Or Oil Change

Although low oil in your engine does not directly cause white smoke to fume out of the exhaust tailpipe, it can certainly have an indirect effect on the depreciation of your engine. When you drive a lot on low engine oil, you may be causing significant damage to your engine parts.

This would eventually lead to failed engine and hence an inventible release of thick white smoke.

In the case of the oil change, a lot of car owners have complained about how they notice white smoke from their hoods when they change the oil. This is possible if you are introducing a kind of oil to your vehicle it is not suited to.

Using the wrong or unsuitable oil can evade the seals and rings, and eventually entering the combustion chamber. This, as you know, could cause thick white smoke formation. Similarly, if you have changed your car’s oil from mineral to synthetic, you may notice white smoke.

Smoke due to low oil and change of oil can only be damaging over time and can be noticeable in the engine’s performance as well.

Different Colored Smokes: What It Means

Although the gas coming out of your exhaust on startup may often go unnoticed, heavy and colored smoke can immediately set off the fear alarm in any car owner’s mind.

With that said, you may be aware that smoke coming out of your car’s exhaust tailpipe does not have to be white all the time. With each color, it indicates a different problem of the engine.

White smoke is a sign of leaky coolant and condensation occurring due to overheating. Whether it is your head gasket that needs repair or the cylinder head, white smoke from the exhaust is a common sight. Similarly, a cloud of blue smoke indicates the burning of oil due to due damaged seals in the engine.

You may also come across grey smoke which is a warning that there is too much oil flow due to a possible fluid leak.

Likewise, many car owners have complained about thick black smoke from their hoods. If your car runs on petrol and you notice similar problems, you may look to replace your fuel injector, or fuel will continue to burn. Nevertheless, in a diesel-run car, black fumes are a sign of accumulated soot in the engine.

Final Thoughts

While is it normal to observe occasional vapor and flames from exhaust, white smoke from exhaust on startup is a sign that the combustion process inside your car’s engine is not right. This is because this white smoke is a byproduct of this process, which should not be as visible as thick smoke.

Condensation on the combustion chambers is normal where smoke you would notice is usually thin. In contrast, coolant leaks are one of the most common causes that leads to dense, white fumes smoking off the hood.

Repairing and replacement of your engine can be your DIY project, only if you have adequate mechanical knowledge of the vehicle. It is always advisable to get a professional mechanic unless it requires mere clog cleaning and bolt fixing.

White Smoke From Exhaust On Startup Essential Knowledge

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