Black Smoke from exhaust Cars – Did you know, that our car
produce power from transmitting heat to rotary power. Heat created by
combustion, and combustion produce several toxic emission. The emisson should
be transparent, because it just produce CO (carbon monoxide) but what hapenned
if the smoke color is black, what causes smoke out fromcar exhaust ? we will
find the answer below article.
If we examine, this smoke is not too disturbing for us who
drive a car inside the cabin. But for other road users , especially pedestrian
this is quite disturbing, the black smoke mean that the exhaust gas containing
several toxic gas like NOx.
What is NOx ?
The NOx is a badly exhaust gas resulting from in-perfectly
combustion. On a normal combustion should resulting CO and H2O. The NOx could
be a toxic to our body if we inhale the gas. For that reason, as the owner of
the car we must usually pay attention to vehicle fumes. Do not let the smoke
from the exhaust is white or black.
Indeed, for cars production over the year 2010 the majority
already carries the EURO 3 emission standard but, the standard is set at normal
engine conditions. If there is a problem with the engine the resulting
emissions could be more severe, in some countries there are even sanctions for
car owners who are smoky.
Causes of Black Smoke From Car Exhaust
As we discussed to above, the black smoke on the car is due
to improper combustion or in other language is incomplete combustion. What
causes incomplete combustion?
1. Too Rich Fuel Mixing
In the combustion engine, we recognize the ratio of AFM (Air
Fuel Mixture) on petrol engines, generally this ratio is around 14: 1 or 14
air molecules compared to one molecule of gasoline. If the ratio changes at 16:
1 or more then it is a lean mix. But if this comparison is 12: 1 or below it
has entered too rich or wasteful mixture.
Rich mixture could hapenned because petrol is not fully
mixed with air molecules, so that when the spark plugs sparking it can burn
gradually and not spontaneously. This is what makes the vehicle smoke smells of
gasoline even feels painful in the eyes. If too much gasoline is burned in the
combustion chamber then consequently the smoke of the vehicle will be much more
concentrated.
In this case, you should suspect the carburetor for first. It
will determine the ratio of air and gasoline.
To overcome this throuble, there are several steps you can
do;
- If this black smoke occurs when idle RPM, then it is due to idle air mixture settings that are less precise. The solution you need to make the adjustment by turning this screw to the left or right to meet the ideal result.
- Check the choke valve, if it is still covered it will make the gasoline too rich.
- If this problem occurs when high RPM or when accelerating it may be caused by damage to the main jet inside the carburetor. The main jet is located inside carb then you have to replace a carburetor unit to eliminate this problem.
- If the black smoke only appears when the car is climbing or carrying heavy loads, then it is the result of a power system on the carburetor that will supply more gasoline thus making AFM richer. For this problem is normal.
2. Injection System Damage
Basically this is the same as the above problem, but the above
problem occurs in a conventional car with carburetor fuel system. For the
second cause occurs in MPV and Hatch class cars are widely used by costumer in
year 2000 and above.
The problem is equally related to AFM ratio. However, fuel
mixing on the EFI engine does not occur on the carburetor, the engine use the
injectors to inject a certain amount of gasoline into the intake manifold. So
the mixture of gasoline and air occurs directly on the intake before entering combustion
chamber.
In this case, the volume of injected gasoline is influenced
by commands from the ECM as the brain of EFI system. In doing the calculations,
ECM uses several sensors to determine the various conditions of the engine.
Data from various sensors will be processed to obtain the required volume of
petrol under these conditions.
From the above, we can see that the success of the injection
system is influenced by the accuracy of sensor readings, the accuracy of ECM
analysis and the condition of Actuator / Injector. If one of the three components
is malfunctioning then the Efi system will erupt and the result can make the
petrol mix too rich.
A rich mixture will occur if the MAF, IAT and MAP sensors are
damaged. This will make the car smoking on every RPM.
- Beside the sensor, ECM damage may occur and determine rich fuel mixture. But if this happens not only smoke problem but the entire engine system will eror even the engine broke down.
- The broken injectors can be a next problem, if the injector keep on or can not closed, the gasoline will alwasy flowing even the ECM command is off. So that the mixture can be very wasteful.
So how to know if there is damage to the EFI system?
When there is damage to the sensor or injector, the check
engine usually light up. If we scan it, it will show the location of the sensor
/ actuator that is damaged. But if you do not have this scan tool, it will be
difficult because there are so many sensors on Efi engine. For that would be
nice to take your car to the official repair shop for chek-up. Generally if
there is a problem with the EFI system, the right solution is a component
replacement.
3. Problematic IAC / Loss
If your car smoke only occurs on idle RPM but your car is
using injection technology and check engine lights are not iluminate. Then it
could happen to the idle speed control or idle air control.
IAC is a door that use by air to flow to the intake manifold
when the throtle is normaly closed, this valve will regulate the air passing
through the idle channel inside the throtle body. So the mechanism when the gas
valve is closed, then the air flows through the idle port and directly into the
intake manifold. But before going out into the intake there is a valve that
regulates the size of this idle channel.
If the valve opens full then the channel will open wide the
result of a lot of air coming into the intake, but if the valve is open
slightly then the idle channel will be narrower so that the air supply will be
restrained.
If the supply of air is restrained, while gasoline is
supplied with the same volume then this will lead to a rich mixture that has
the potential to produce concentrated exhaust emissions. Generally if this
problem arises, there are other engine symptoms that follow such a difficult engine
start even suddenly Off when idle RPM.
The solution, you need to open the IAC located on the
throtle body. Then clean the valve and clean the idle channel using the Carb cleraner,
this fluid will remove the crust and dirt on these two components quickly.
4. Dirty Air Filters
For the last cause of the air quality supplied from the
filter. The filter has a function to clean the air from dirt, lest it pollute
the air into the intake and inhibit intake airflow.
Filter work by blocking the particle on a outer surface of
filter, in a long time used the particle will settles and there are two posibly
causes. First, the settles particle will be resistance to the air hose so the
air flow will hamperred. The second cause, filter element will broken down so
the dort air will flow inside the air induction. If there are dirt or dust
inside the air induction, then it will clog several important port in the air
induction inlcuding idle port and injector chanel.
Indeed the filter does not directly make the car smoke so
black but dirty air filter will be the initial cause that make several damages for
example on MAF, IAT and MAP sensors located along the air induction hose. Dust
or dirt attached to the sensor surface will obviously affect the accuracy of
sensor readings.
The best solution of this problem is the prevention of
damage to the injection system on the engine, ie by tuning up the engine on a
regular basis. Most importantly, keep clean the air filters regularly and if
filter conditions are not possible to clean then you should replace them with
new ones.
Cleaning the engine combustion is also not less important,
this cleaning you can do yourself with the material combustion chamber or do it
your trusty workshops.
Similarly a brief article on the causes and how to fix or
resolve black smoke that out from car exhaust, hopefully add to our insight and
useful for all of us. Don’t forget to share so that more and more people
knowing about the insight.