Knowing your Car: Diagnosing the Different Types of Exhaust Smokes

Exhaust Smoke

Sure, it is normal for your car to blow out smoke—after all, it has an exhaust system that pulls burned fuel away from combustion and out of the engine. Just like the human body, this is exactly how it should be: the body intakes fuel and secretes all wastes.

Connected to that, we have one more similarity between the human and the auto body systems: the wastes of both have a measure for what is “Yay, normal!” and what is “Uh, oh!” These you have to know so you can prevent an illness from happening—and we’re not only talking about the human body.

So what exhaust smoke tell us about the current condition of our vehicle? And how do we DIY diagnose the possible illnesses? Continue reading to find out!

Blue Smoke

Burning Blue

That’s not magic! It’s evil! And you have one thing to check: oil. Make sure that oil is not leaking out of its chambers and creeping into holes, trying to get into the engine. Because with blue smoke, it is likely that such is the case. Either your piston rings or your valve guide seals are worn out since the oil is not contained where it should be.

What this does to your car is evil. Not only does it cause rough starts (and the potential ruining of your car’s spark plugs), but it also adds to the environmental trauma that your exhaust already poses in its normal state.

Don’t panic yet. This is a simple enough problem to solve. You just have to replace the piston rings or valve guide seals, whichever is retired. You can also check if the car is turbocharged, which must direct you to replacing the blower.

Black Smoke

Black Widow

For humans, this means far from good. Now for cars, well, it may only mean that your engine is burning too much fuel—like you releasing a big bean-charged intestinal gas.  Because your fuel is involved, you have to check the following parts in order to determine the cause: fuel injectors, sensors, and the fuel-pressure regulator.

Now if none of these are causing the problem and the black smoke is still there after ignition, try checking if your air filter needs replacing or if your carburetor choke needs repairing.

White Smoke

White Apparition

No ghost here ladies and gents, but it is a reminder telling you to check your car. So be cool, especially if the out is cold because that’s normal. Besides, you can fix this, too!

It’s simple: once again, go to where the problem is coming from. In this case, it may be the vacuum modulator that needs to be replaced since it’s letting transmission fluid enter the intake manifold. Another problematic part may be the cylinder gasket or the cylinder head, which you may have to resurface for careful inspection. It may also be the engine block, so better check that as well.

Gray Smoke

Gray Matter

Now this can be a tricky problem to diagnose simply because its symptoms are the same as that of blue smoke. Your problem may come from oil getting burned up, plus more!

It can be the automatic transmission fluid getting burned up in the engine, which further leads to the vacuum modulator being faulty. Or, it can also be the PCV valve getting stuck, which leads to oil leaks, too.

Now that you can diagnose the problem with your car, have it a go. You can always ask a mechanic to help you, but if you find the challenge puny as an auto buff, surely you can do the checking for yourself. Just be careful—or you might turn into smoke.