White Smoke From Exhaust

White Smoke From Exhaust – When Idling, Accelerating & Startup

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Paying close attention to the color of the smoke coming from your car is as important as servicing the vehicle.

If you are having white smoke come from your exhaust while idling, startup or accelerating it could be an oil leak, bad fuel injector, or various other reasons. White smoke may seem harmless in normal conditions, but it could a sign that something is seriously wrong with your automobile. It would be nothing to worry about if it’s thin and vapor-like, but when it comes out thick, you need to check the vehicle. If you have no idea what the white smoke from the tailpipe means, read this guide for all the helpful information.

Causes of White Smoke From Exhaust

The thin white smoke coming from your tailpipe may not necessarily be a sign of trouble. It could be the accumulation of condensation which evaporates when you start the engine and create a warm environment. Thin white smoke is common on colder days and should clear up in less than a minute. If it doesn’t, you know something is wrong.

If the smoke comes out thick and fast, you could be facing a broken cylinder head, allowing the coolant to leak out, and getting mixed with engine oil. The coolant contaminates the oil, causing the emission of white smoke from the tailpipe. It can also happen if your car has a damaged coolant tank.

White Smoke From Exhaust While Idling

The thick white smoke coming out of the exhaust pipe while idling could be the result of an oil leak. The oil oozes out of the piston rings or valve seals and flows into the internal combustion chamber with the fuel. The mixture of fuel and oil produces thick white smoke when combusted.

A faulty engine control unit can also cause thick white smoke from the exhaust when idle. When the engine control unit develops a glitch, it may throw off the timer of the fuel injector. It doesn’t mean the fuel injector has any problem, but it’s the timing that is wrong.

White Smoke From Exhaust on Startup

White smoke from exhaust on startup could be the result of a bad fuel injector. The fuel injector shoots fuel into the internal combustion chamber at the right time. A faulty fuel injector would produce white smoke it wouldn’t inject the right amount of fuel into the combustion chamber at the right time.

But you may not have to worry so much if the white smoke on startup is thin and lasts only a minute or less. This is because the white smoke may be the condensation in the tailpipe which vaporizes when the heat of the engine spreads through the exhaust system.

White Smoke From Exhaust

Engine Coolant Leaks

One of the most prominent causes of white smoke when accelerating or on startup is engine coolant leakages. The coolant could leak if the coolant reservoir tank suffers damages or cracks. The damage can occur when a mechanic is fixing other problems and accidentally applies too much force on the coolant tank.

Engine Intake Gasket Problems

A gasket goes in between the intake manifold and the cylinder head to provide a seal. The intake manifold is responsible for the delivery of a mixture of air and fuel to the cylinders. A problem with the intake manifold would mean challenges sealing the two components, air, and fuel.

One symptom of problems with the engine intake gasket is an overheating engine, which eventually leads to the production of thick white smoke from the tailpipe. You may not see into the gasket, but your dashboard will notify you about your engine overheating. But you will know that the engine coolant could be leaking into the manifold.

You may also experience loss of acceleration when you step on the gas if the engine intake gasket has problems. The most likely symptom would be white smoke from the exhaust when accelerating. You may get a little power at first but a few moments later, the acceleration stops and starts again because the leaking coolant has contaminated the fuel in the combustion chamber.

You shouldn’t continue driving your vehicle in this condition because it may cause more damage to your engine. It is also dangerous because the engine may stall without warning, and get you stuck in the middle of a busy highway. When these signs occur, it’s time to replace the intake manifold immediately.

Cracked Cylinder Head Problems

A cylinder head mates to the engine block, sealing off the combustion chamber where the engine burns fuel to provide power to your vehicle. It also houses the valves that supply fresh air to the combustion chamber, and more valves direct used air out of the engine. A cylinder head can crack under extreme conditions and show similar symptoms to those of a blown head gasket or a cracked block.

Internal combustion engines heat up pretty quickly because much of the energy resulting from the combustion of fuel and air converts to thermal energy. It’s their design that causes this phenomenon and nothing much you can do to mitigate it. As such, the engine may overheat and crack the cylinder head.

Other conditions that may make your engine to overheat include the following:

  • Failure of the water pump causing an improper flow of the coolant in the engine.
  • A failed thermostat which may block off the coolant from accessing the engine.
  • Air in the cooling system which allow the development of hot spots causing one part of the engine to become hotter than other parts.

White Smoke From Exhaust Solutions

Thick white from your exhaust spells doom for your vehicle if you don’t take measures to address the situation. Here is what you can do before calling in a professional mechanic:

  • Inspect the intake gasket for any leaks or rust.
  • Check the head gasket to see if there is a crack causing the coolant to enter the combustion chamber, resulting in thick white smoke from the tailpipe.
  • Look for cracks in the cylinder head.
  • Replace damaged parts, such as the cylinder head since you can’t repair it.

Final Thoughts

Thin white smoke coming out of your exhaust could be normal, but when it gets thick and persists, you need to start paying attention to your engine. Check if the cylinder head or the engine block has cracks, causing the coolant to leak into the combustion chamber. If you need more information on white smoke from your exhaust at startup, idling or when accelerating, you can Contact Performance Muffler if needed.

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