Cars with combustion engines emit pollutants, and that is a fact there is no point in disputing. Sometimes you can spot a somewhat older car on the street trailing smoke that is white, black, grey, or even blue. What does it mean when a car is smoking? Can anything be done about it? Read on.
A smoking car - a bad sign
Smoke coming out of the exhaust pipe is a harbinger of a fault. There is no situation in which visible exhaust fumes signal something good. The worst-case scenario is, of course, the black clouds that trail behind the car and, on top of polluting the air, also disorient other drivers. This does not mean, however, that you can dismiss white or blue smoke. Each of them is a sign that something is wrong with the car.
A smoking car - the individual colours of smoke
As you could already read above, the colour of the smoke may vary depending on the fault you are dealing with.
The car smokes white
White smoke in most cases means that the head gasket or the cylinder head itself has been damaged. White clouds are caused by a leaking cylinder head and by the fact that coolant is getting into the cylinders. You will also notice a drop in engine power and an intensity of smoking directly proportional to the engine load.
The simplest way to check whether you are dealing with a cylinder head failure is to check the coolant level. Also test the pressure in the system while driving as well as the tightness of the head gasket. You can do this using a special tester that is inserted into the coolant expansion tank.
The car smokes grey
Grey smoke is a sign of an overly rich fuel mixture. If the computer feeds too much fuel into the system relative to the amount of air, the engine will have trouble reaching the proper operating temperature.
The fault can be diagnosed by testing one of the sensors (most often the engine temperature sensor). Replacing the sensor costs a few hundred zlotys, but if you want to reduce costs significantly, you can always use a used part.
The car smokes blue
Blue smoke is most often a problem with oil burning. So look for the source of the fault in the compressor, from which oil is transported to the intake system. The cause of blue smoke from the exhaust pipe can also be worn piston rings or valve guides. In such a case, prepare for a costly reconditioning or replacement of the entire turbocharger. If you are unlucky, even a complete overhaul of the entire engine may turn out to be necessary, and that already means costs running into the thousands of zlotys.
When it comes to blue smoke, it is worth checking the oil level regularly. Specialists recommend carrying out a check every 2-3 refuellings. If you notice that the oil is “disappearing”, be sure to see a trusted mechanic who will diagnose the problem.
The car smokes black
If black smoke is coming out of the exhaust pipe in your car, there is a high probability that you are dealing with a problem with the injectors. This is about too low an injection pressure or leaks in the system. The injection systems and unit injectors used in modern cars are very sensitive to the quality of the fuel poured in, which is why faults are not uncommon. Unfortunately, in the case of problems with these components, you have to brace yourself for a costly reconditioning or replacement. Set aside several thousand zlotys.
Black smoke can also herald a turbocharger failure, especially if you have noticed a drop in power and louder operation. A damaged turbine rotor, compressor wheel, or variable-geometry vanes are components whose failure can also be the cause of black smoke.
Why is my car smoking - conclusions
As you can see, smoke coming out of the exhaust pipe should raise your alertness in every case. After all, it is not a normal situation. Regardless of the colour of the exhaust fumes, a visit to the mechanic and a consultation on the condition of the vehicle is essential. Remember that a neglected problem can turn into a serious failure, getting rid of which will require enormous financial outlays.
