How To Diagnose Black Exhaust Smoke

March 30, 2019MechVibesblog

Hello and welcome, today we will be outlining few steps you can take on how to diagnose black exhaust smoke and other related issues.

When ever your vehicle start smoking black and badly is advisable to quickly slow down or park the vehicle to prevent unexpected bills.

You can also call roadside assistance for help. Most individual drives safely to the dealership whiles others call their private technicians to help them solve the issue at hand.

If this view, you will learn and diagnose why vehicle smokes, major causes and procedures to get it solved. Subscribe to our newsletter in other not to miss our fresh content.

Major Causes In Diagnosing Black Smoke

  • Stuck fuel injectors, fuel return lines and pressure regulators
  • Clogged Air filters
  • Faulty MAF sensor
  • Bad EGR -Exhaust Gas Re-circulation

Symptoms Of Black Exhaust Smoke

  • Black smoke from exhaust tail pipe.
  • Less torque.


Porsche And Their Fault Code Meanings

Solutions To Diagnose Exhaust Black Smoke

1. Regular use of fuel treatments

Regular use of fuel treatments and additives can enable vehicle perform well and risk-free in the near future. These treatments helps reduce debris or particles found in the fuel. The are completely claim to improve your car’s economy and performance.

These additives are available for petrol and diesel engines and promise a wide range of benefits from keeping injectors and intake valves clean.

Moreover, these additives helps vehicle run smooth and free from smoke by removing water from the fuel and prevent particles from entering into the fuel injectors and return fuel pipe lines.

Regular application can help your vehicle stay healthy and risk-free of black exhaust smoke.


Beginning As a Mechanic

2. Clogged/dirty air Filters

The vehicle needs right amount of air to produce a complete combustion process, therefore checking for clogged/bad air filters can be a great step to prevent vehicle from smoking.

When filters become too old, they began to loose it lifespan, causing vehicle not to perform well. Enough debris been clotted inside the filter, blocking the passage of fresh and clean air.

Also, make sure air filter box are cleaned properly before fixing a new one. You can use high pressure air to blow every dust or particles inside air filter box.

3. Faulty MAF sensor

Check for faulty MAF sensor.

When your Mass Air Flow Sensor is faulty or short to circuit, it can also cause vehicle to smoke. Most times they easily get disconnect from their sockets.

Its advisable you check on the harness as well, they usually have breakages or loose of contact in wires, checking for continuity of the wires will also help in diagnosing faulty MAF sensors.

This can be done by disconnecting the socket that goes directly to the sensor whilst engine is running to see how it will perform.

If same results, it advisable you replace the sensor.

4. Bad EGR(Exhaust Gas Recirculation)

EGR (Exhaust Gas Re-circulation) play a vital role in vehicles,they are part of the vehicle emission system and helps to build pressure(back pressure).

They are purposely built to re-circulate exhaust back into the combustion chamber for a complete cycle. They have flaps been installed in them, they mostly open and close for the passage of burnt gases to be recycled back into the system.

These EGR get stuck along the line and hardly perform well. Checking for a bad EGR can also help in resolving the issue.

4. Weak piston rings

Pistons rings needs to be check and replace if bad or damaged.

Piston rings also worn out after longer period of using vehicle. These rings are design to hold pressure in the combustion chamber.

If piston rings worn out, they hardly hold pressure in the combustion chamber.

Is always good to perform compression test on vehicle to know the pressure built in each cylinder.

Lets us know your views, share with us in the comment section. You can share this post if found helpful.

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