Why is My BMW Engine Smoking?

This blog post will tell you about what it means if your BMW engine is Smoking. It will also cover the causes behind smoking. Moreover, what to do if your car engine is smoking?

Why is My BMW Engine Smoking?

If your BMW is smoking while you drive, then there might be something wrong with your engine or other parts of the BMW. 

Overheating causes smoke to frequently escape vehicle engines. Defective wire casings, hot residues on the engine block, and hot liquids like oil, transmission fluid, and brake fluid can all contribute to this.

Some of the common causes include:

  • Defective coolant system
  • Leaking head gaskets
  • Burnt electrical wires
  • Broken pistons
  • Faulty fuel valves

What are the Causes of Smoke in BMW?

We’ll go over some of the potential causes of the smoke emanating from BMW below:

Black Engine Smoke

When your engine starts to emit black smoke, too much fuel is likely being burnt. A clogged air filter is another potential culprit. Both flaws are typically simple to address if you identify them early.

Damaged Fuel Injector

Fuel injectors spray a high-pressure mist of gasoline or fuel into the engine. They may clog up with debris or poor fuel, leak as a result of seal wear and strain, or both.

Damaged Fuel Pressure Regulator

As the name implies, this component of the fueling system controls the pressure at which gasoline and diesel are given to your car.

The cost of a replacement depends on whether the part is located within or outside the gasoline tank.

If the gasoline pump also has to be replaced, you should ask your neighborhood mechanic about it.


A carburettor is used in older cars to combine the fuel and air. You’ll notice dark smoke when the component malfunctions and feeds the engine too much gasoline or fuel.

Your automobile will be consuming too much gasoline and emitting too many emissions if the issue isn’t checked by a professional as soon as feasible.

White Engine Smoke

A coolant leak is typically indicated by white smoke coming from your engine. Any of the following issues could be the root cause:

Cracked radiator/coolant hoses

You may be able to observe the damage for yourself by simply opening the bonnet. Over time, hoses leading to and from your radiator might collapse, bulge, and shatter.

It is advisable to have a professional complete the work because the parts should be affordable to replace.

All of your engine’s essential components are held together by engine blocks.

 Broken Engine Block

Low temperatures might cause coolant to freeze and push up against the block’s walls, creating tiny fissures.

Despite being rare, manufacturing errors could have left some engine block portions thinner and more prone to damage.

For little cracks, you can try using an engine block sealant, but for anything more significant, you should go to a reputable garage.

A mechanic might have to reweld certain areas of the block or fix it using a process called cold metal stitching.

Beware, the repair is highly expensive, and it can be more cost-effective to purchase a new vehicle.

Exhaust Smoke

Smoke from the exhaust is likely to be the first thing you notice. It is available in three hues:

  • Black: A strong fuel stench may accompany the black smoke. This could indicate that the engine is receiving either too much fuel or insufficient air.
  • White/Gray: white smoke indicates the presence of water in the cylinder, which may be the result of a coolant leak in the intake or head gaskets.
  • Blue: Smoke that is blue indicates that the cylinders are burning oil. This could occur if the piston rings are worn or if oil enters the engine through an intake valve that is leaking.

You can experience a reduction of power or fuel economy with any of the smoke hues.

Electrical Smoke

The electrical system of your BMW could be the source of the final sort of smoke you observe. The majority of the wires in your car are covered and insulated, therefore it’s not very common.

Under the hood, though, there might be white smoke and a strong, pungent smell that nearly seems to bite. When the smoke is coming from a hot wire, that will most likely occur.

Even though it’s rare, if the alternator is shorting out or is entirely fried, smoke could be flowing from it. If that occurs, your vehicle’s dashboard may also display a low voltage or check engine light.

What to do If Your BMW is Smoking?

If you experience smoking in your BMW it does not mean that it’s going to fire but it still be dangerous. Here’s what you should do first if you ever see smoke coming from under your hood:

  1. Check your temperature gauge right away. See above if there isn’t any overheating.
  1. Even if there isn’t an open fire, pull over as soon as you can if the temperature is high.
  1. Open the hood, but avoid attempting to support it. Your hood will be unbearably hot to the touch if it overheats.
  1. Get out of the car and remove all other occupants from the area. As much as it is safe for you to do so, warn other drivers.
  1. Call the fire department and let them know there is a fire.

Other articles about  BMW you may be interested in

BMW 3 Series or Mercedes Benz C Class?

What is the cost of ownership for BMW and Mercedes Benz?

Why My BMW Engine Won’t Start?


This blog post addressed the problem of smoking in BMW. We have discussed various causes that can lead BMW engines to smoke. Also, what are other causes of smoke in BMW cars other than the engine. Moreover, we have mentioned some tips that if you encounter smoke in your BMW what you  should do first.

Frequently Asked Questions (FAQs): My BMW Engine is Smoking.

Smoke coming from the engine area.

Oil pouring from the valve cover gasket onto the exhaust manifold is most definitely the source of the smoke. a fairly frequent maintenance problem. The valve cover gasket can be removed and replaced quite simply. No big deal; you can still drive, but fix it as quickly as possible. 

Why is my E60 BMW Series 5 producing white smoke?

White smoke is most likely caused by faulty or worn oil-control rings on the pistons. This is not an unusual or unavoidable condition.


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