There are several issues that can lead to black smoke coming out of your engine. It's most often caused by a clogged air filter, poor oxygen sensor, etc.
Below we have mentioned some of the reasons for black smoke coming from car exhaust.
it is no doubt one of the causes of black smoke from a dirty exhaust is an engine with poor filtration. This leads to reduced airflow, which promotes accumulation within your car's system, including damaging spark plugs, among other parts.
Bad oxygen sensor
A bad oxygen sensor can cause a lot more than just black smoke. It will also make your car run less efficiently, which means it consumes fuel at a higher rate and has hard starting problems as well since the engine doesn't have enough information from its sensors about how much air is being mixed with fuel inside.
Faulty Auto Computer
There are many causes of black smoke coming from your car, but a faulty auto computer is one common culprit. If you notice any of these telltale signs - such as noxious blue or gray exhaust fumes with an unpleasant odor, then it's time to take care of your vehicle!
Clogged Air Filter
When you're driving and notice black smoke coming out of your exhaust, it could mean that there's a problem with the air filter. Have any other cars been experiencing this too? It might be time for an inspection!
Faulty Fuel Injector
A fuel injector is a very important part of your car's engine found at the head. It ensures that only clean, pressurized gasoline flows into each cylinder with pinpoint accuracy from this device! When accelerating, a clogged or faulty injection system will emit black smoke because it isn't spraying enough mist to coat all surfaces effectively.
MAF (Bad Mass Airflow) Sensor
The mass airflow sensor is a crucial component of an engine because it allows for the correct amount and distribution of air/fuel mixture. This can be compromised by bad MAFs, which register more incoming flow than what's actually available in order to produce unburned fuel within your vehicle.
EGR (Dirty Exhaust Gas Recirculation) Valve
The EGR valve is a critical component of the engine that prevents black smoke and reduces its temperature. Improperly working EGR valves can lead to malfunctions, which will produce more harmful gasses and black smoke. Before you decide on replacing it with another one consider cleaning first!
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