8 Reasons Grey Smoke from Diesel Exhaust When Accelerating

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It is common and common to see white, black, blue, or gray smoke coming out of a car’s exhaust system. But sometimes the level of smoke coming out becomes excessive. Here are some reasons to worry. Have you ever noticed the grey smoke from diesel exhaust when accelerating?

If so, there is nothing to worry about. Because it has some symptoms that will tell you what caused it. The main cause is oil leaking or a jammed turbocharger. Moreover, if the smoke exits densely, there is a problem with water or coolant ending up being heated while entering the combustion chambers.

However, there is no point in exaggerating, let’s come to the main discussion. Today you can learn from this article about the reasons behind the gray smoke and its solution.

8 Reasons Grey Smoke From Diesel Exhaust When Accelerating

If you do not understand why this kind of smoke is coming out then you will not find a solution. For this reason, you have to find out the exact reason. Here are a few reasons why gray smoke can come out when accelerating.

1. Oil Leakings

Oil leaks are common and one of the main causes of gray smoke. Whenever there is an oil leak, assume that your engine gaskets have deteriorated. Also, oil pan leaks and unsuitable seals are the other culprits behind oil leaks. If you continue to drive with oil leaking, the engine may be damaged for a while.

And because of this, different types of polluting fumes come out. One of them is the gray smoke. Especially in the diesel exhaust system if there is oil leaking, surely, the grey smoke comes rapidly while accelerating.

2. Jammed or clogged turbocharger

Gray smoke, excessive burning of oil, and slow acceleration are usually caused by a bad turbocharger. An excessive rate of gray smoke is seen to come out when the turbocharger is bad.

So it should be understood that whenever you see the origin of gray smoke, then check this part a little. It’s not just creating smoking rapidly. As long as you drive with this jammed or bad turbo, your engine will slowly break down. And as a result, you have to pay more to repair it.

3. Transmission system leak

Most cars have a gearbox. If your car also has a gearbox in your car, take care of it. It is often seen that due to a lack of proper care of the gearbox, it leaks and this leads to various complications.

Transmission system leaks are caused by repeated excessive wiring. This can also be due to pan leaks. In some cases, various waste and heavy metal feces are stuck for a long time, which can also cause the transmission fluid line to leak.

4. Damaged or faulty PCV valve

If there is a problem with the PCB, then there may be a problem with your whole system. Driving with a damaged PCB valve is just as risky as it emits a lot of gray fumes. Other problems include excessive oil leakage, oil leaks, air filter blockages, and, most importantly, reduced system performance.

The valve is jammed with a variety of organic and inorganic particles, debris, and road dust. This prevents it from properly transporting the oil to the engine and bringing it back to the cylinder from the intake manifold.

This results in the formation of large amounts of carbon and carbon-like particles. The result is an excessive amount of gray smoke.

5. Filthy air filter

Clogged or filthy air filters are considered to be another notable cause of harmful fumes. When the air filter gets dirty, the air supply at the right rate also shuts off. As a result, it increases the amount of unburned fuel that is subsequently stored as residue. Another problem is that it does not produce enough spark and increases the engine’s misfire.

6. Worn cylinder walls

The rotating crankshaft takes the oil from the oil pan and throws it on the wall of the cylinder. This makes the wall wet and clean. However, since the valve is closed, carbon deposits can break and cause adverse reactions on the cylinder wall during combustion. Which is then emitted in the form of black or gray smoke with an exhaust system.

7. Worn Piston Rings

Damaged piston rings are responsible for creating any type of fume whether white or black or gray or blue. When the piston rings are damaged, the piston cannot properly circulate and purify the oil. As a result, oil is not easily refined.

8. Engine-burning oil

When the engine burns fuel at a higher rate, some foul smoke comes out of it.  This is because when the engine burns oil at a higher rate, it emits carbon indiscriminately.

How to Get Rid Of Grey Smoke From Diesel Exhaust System?

If there is a problem, it will be solved and this is normal. If you want to get rid of this kind of problem then fix the following things. Hopefully, you can get out of this problem very quickly.

Check the oil conditions

So first you need to know about the condition of the oil in the fuel tank or in the oil tank. Try to remember how long ago you inserted the fuel. If it happens more than a month ago, it is mandatory to change your fuel.

Replace the worn piston rings

As it is said that worn piston rings are the main culprit for billowing any kind of smoke, you need to change it immediately. So inspect deeply and carefully to check the piston rings and if needed replace new ones.

Repair the turbocharger

Clogged or jammed turbochargers can ruin your internal combustion and ignition system. When this turbo is bad or jammed it can’t work properly to circulate any air or fuel at a certain rate. So examine your turbocharger and fix it soon.

Check the transmission fluid

Transmission fluid helps to transmit the oil from the fuel line to the engine and other valuable parts. It also allows the engine to lubricate fast and make the internal parts speedy. So check this if you notice grey smoke from your exhaust when accelerating.

Clean or replace the air filter

When there is an air filter block, it becomes very difficult for air to be transmitted. In this case, the harmful air from inside cannot come out and the necessary air from outside cannot go inside. So take it to a mechanic and get it fixed.


It is not a significant problem if it comes out in very small quantities. When you accelerate, sometimes this kind of smoke comes out, especially from the diesel engine. Clogged turbochargers and excessive rate of oil leaking are some of the reasons for the grey smoke from diesel exhaust when accelerating. All this has been discussed in this article. Happy Riding With Experience Any Bad Smoke especially Gray Smoke.

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