What the Smoke from that Exhaust pipe is telling you
Cars at a traffic lights approach as drivers negotiate through the streets.
Just like you can get food poisoning from that random rolex, your car can develop issues that are only apparent when examining the plumes of smoke coming out of the exhaust pipe.
Furthermore, you can pinpoint the problem by colour of the smoke. If the car is in good shape, exhaust smoke should be nearly undetectable.
If exhaust smoke is visible, there is likely to be a problem, which will need a mechanic to deal with.
The inside of an engine is literally a furnace, but here is the thing, smoke rarely comes from the engine, under the bonnet that is, and if it does, then it is critical already.
An oil seal might produce smoke caused by oil dripping on a hot manifold. If the leak is large enough, you are likely to see the oil dripping under your car.
If it is a fire under your bonnet, you would see smoke, but flames would quickly follow that, resulting in a very dangerous situation. If this happens, quickly exit the car and move far away.
Much as there is furnace-like situation inside the engine which definitely produces residues, there is clever plumbing all the way to the exhaust.
While the exhaust smoke may signify a serious problem, there is a silver lining— the colour of smoke is an indication of what might be wrong. This helps make the diagnosis quick and timesaving.
Typically, there are three kinds of smoke: black or grey, blue, and white.
Black smoke
Starting with black smoke. This results from an abundance of fuel in the combustion cycle. This is also called “running rich.” Black exhaust does not always indicate impending doom.
If your car emits a little black smoke in the morning at start up, but clears up as the engine warms, do not worry. It is normal for some cars.
When the engine is cold, it needs a little extra fuel to maintain the demands the driver is asking of it.
If the black smoke continues after the car warms up, then there is cause for concern. This could be anything from the spark plugs to anything within the fuel-air system.
One of the first culprits to look out for, and perhaps the least thought about, is a dirty air filter.
An air filter stops airborne contaminants from being sucked into the car’s engine and clog it. If it gets congested there is inconsistency in the amount of air entering the engine.
While there might be secondary engine systems, which may compensate for this, a dirty air filter should always be your first check.
If the problem persists, it is an indication that your car’s air-to-fuel ratio is off, it is burning too much fuel than it should. Anything along the fuel system including the fuel pressure regulator, fuel injectors, fuel return line, et cetera, could be a culprit.
White smoke
This kind of smoke can be nothing to be concerned about if it is thin, like vapour. It is probably the result of normal condensation build-up inside the exhaust system.
The smoke disappears quickly and is usually experienced in the morning. But after warm up, thicker white smoke is a big problem that results from water mixing with the exhaust gases or in the combustion cycle.
This can be because of a serious issue like a blown head gasket, a damaged cylinder head, or a cracked engine block, all of which are costly repairs. Do not ignore it as the problem could become far worse.
While chatting online with Donald Lule, an instructor at Nakawa Vocational Institute’s Motor Vehicle Section, he cautioned that even a small leak in the water cooling system can lead to overheating and serious risk of damage to the engine.
Water can also mix with oil and cause serious headaches for you.
An engine essentially consists of an engine block and a cylinder head. The block is where the cylinders and coolant passageways are located, and the head is where the valves reside.
The head gasket is placed between the two to seal the connection. If it is damaged or compromised, coolant can find its way into the combustion chamber.
For a damaged cylinder head, you can have a good mechanic replace it but it is the kind of job that is involving and requires patience.
After a crash-course in the car engine structure, Lule says for a damaged engine block, you have to accept that as virtually impossible to repair. A replacement engine is the only reliable remedy, but that can be expensive and sometimes not worth the investment.
Depending on the age and value of your car, you may consider cutting your losses and buy another car.
Blue smoke
Thick blue smoke shows burning oil, which means that oil is somehow leaking into the engine’s combustion chamber. This can cause a wide range of issues from reduced fuel economy to less-than-expected acceleration.
The valve guide seals or piston rings are worn out, and oil is leaking past from where it should be lubricating the moving parts, to the combustion chamber where it is being burnt up with the fuel. If you see blue smoke, check your oil regularly and watch for consumption issues.
While the issue should normally require immediate attention and expensive repairs, including replacement of internal parts, if your car is old and the leak is minimal, it can be carefully managed by topping up the oil on a regular basis.
Along with environmental damage, burning oil can cause rough starts, as the process can spoil the spark plugs.
The problem with your engine shall ultimately depend on the source and cause of the smoke. Given the number of variables outlined above, costs can vary quite a bit. By taking care of the issue promptly, you may save yourself several emotional and financial headaches down the road before whatever is the cause of the “smoking” worsens.
