A smoky exhaust can be a major cause for concern as a vehicle owner. It doesn’t take long before you come across an automobile with significant smoke emissions. In the majority of the cases, a smoky exhaust is a clear sign of neglect. It means that the vehicle is poorly maintained – something to look out for when purchasing a used car.
But what does it mean, especially when it comes out of nowhere? Is it a reason to be worried?
Reasons for a Smoky Exhaust
Some repairs can cost you an arm and a leg, especially if you don’t head off a likely problem at the pass. If you notice some unusual smoke coming from the exhaust, you should scrutinize it. Does it appear when accelerating or when the vehicle is stationary?
Excessive black smoke from your contemporary diesel vehicle indicates something’s wrong in the exhaust system or injectors. This smoke is usually typical for old diesel vehicles.
It’s a bit different for gas vehicles. Black smoke emissions from a gasoline-powered car can be from excessive fuel going into the engine. The main culprit is a faulty electronic sensor or a dirty air filter.
However, blue-grey smoke could be a sign of a more serious problem. For example, you could be dealing with worn-out cylinder bores or piston rings, or even other engine components. The problem could also be the turbochargers or worn valve seals. White smoke could indicate engine coolant leak and which is a more serious issue.
On the other hand, grey smoke could be from a transmission fluid leak or PCV valve failure, especially if you are driving an automatic car.
What to do
If a smoky exhaust becomes the order of the day, the game plan is usually to take the vehicle for diagnosis. Remediation is critical at this point to avoid further damage.
