What are the signs of a bad engine?


Cars are not built to last forever, and pretty much every car component is bound to break eventually. Even so, it is essential for you to proactively solve these issues while they are not able to cause any further damage.

The engine is the beating heart of any car, it makes the car move and it also charges your battery, and without it, your car is useless. That being said, it is paramount that you service your engine as recommended by the manufacturer to keep it in its optimal state.

The most obvious sign that something might be wrong with your engine is the engine warning light which usually illuminates whenever the ECU detects an engine issue. Furthermore, loss of pulling power, bad fuel efficiency, and weird noises are also definite warning signs that something is wrong.

Additional commonly experienced defects are misfiring or the engine not being able to spin freely. Weird odors, increased temperatures, excessive amounts of exhaust smoke are also indications that something is not as it should be.

Check engine light

There is an abundance of reasons why a check engine light comes on. Some of them are easily fixable and not even worth mentioning, while others can be serious hints towards your engine being at risk. It is best for you to take your car in for a diagnosis, even if you think that the issue is not all that serious.

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Some people, including myself, have a constant check engine light warning sign on our dashboards because we know that it’s a faulty sensor that has nothing to do with anything important. However, if something does break, we might not be able to detect it because our check engine light is already on.

Engine power loss

An engine uses a compressed air and fuel mixture to create controlled explosions which translate into mechanical energy which makes the car move. During this process, four specific things happen, and they are called the intake stroke, the combustion stroke, the compression stroke, and the exhaust stroke.

For your engine to deliver optimal power, all of these have to work in perfect harmony. If they are not, it is likely that one of these four strokes is not operating as intended. To remedy this, take the car in for a service, and don’t drive the car until this is solved.

Gas mileage is worse than before

As previously stated, in order for an engine to deliver its power at a continuous rate, many engine components have to be in sync. If for some reason you are constantly getting poor fuel economy, chances are that your compression stroke is malfunctioning.

Be sure to take your car in for a fuel system service, and also make sure that you are not suffering from leaks. Some reports even say that this could lead to terminal engine issues, and that’s not something you want to experience.

Rough sounding engine

If you experience your engine running rough or unbalanced, chances are that either your spark plugs are a bit too old or your engine might be clogged up. Both of these can be easily fixed at any experienced service shop.

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It is never a good idea to leave a rough engine unintended as it can exponentially worsen the problem. Also, be sure to check in on your battery and if you got the correct octane fuel as both of these can also sometimes roughen up the engine.

Peculiar engine notes

Probably the scariest and most common sign of a bad engine is a weird noise such as knocking, hissing backfiring, or popping. These usually occur because of an abnormality inside the combustion chamber. And if you don’t attend to these issues proactively, your engine might be at great risk.

Something like a loose bearing or a malfunctioning piston can destroy your engine completely, so it’s never a good idea to drive such a car. Whatever it may be, make sure you take your car in for an inspection as soon as possible.

FAQ Section

What are the signs of a bad transmission?

Your engine and your transmission are very closely related. However, the transmission itself is also prone to breaking, and it’s a good idea to know what to look out for if that ever happens. If your transmission struggles or completely refuses to switch gears, park the car up and call a mechanic.

Furthermore, if you sense any burning noises, also be sure to park the car up immediately. Slipping gears, leaking fluid, or clutch dragging are all definite signs that your transmission needs attending. Because the transmission and the engine are so closely related, if you do feel that something is out of place, don’t drive the car.

Are electric engines more reliable compared to traditional combustion engines?

We are only at the very begging of the electric engine, and it’s not a smart idea to suggest that an electric engine is way more reliable than a combustion engine. However, an electric engine does have fewer moving parts which mean that there are fewer issues associated with things breaking.

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Electric engines tend to lose less energy due to friction which makes them more power efficient and balanced. As such, they are less likely to act unpredictably. Be that as it may, it is still too early to tell how well do electric engines do long term.

How long do car engines last?

Many people believe that engines can last upwards of 8-10 years or 150-200k miles. Although such numbers are large, some engines can last even more than that. There are countless examples of people driving their 500k mile cars without needing a full engine rebuild. These instances are rare of course, but it shows how well some engines operate after a couple of years.

However, such engines are increasingly difficult to find these days because today’s engines are overly complicated and overbuilt thanks to restrictive emissions regulations. Many engines nowadays are turbocharged, supercharged, and boosted by an electric engine. And if you pair that with many emissions technologies, such engines can’t last all that long.

Marko Mikulic

Why do you love writing about cars? I love writing about cars as cars are a huge personal interest of mine. I was raised in a car enthusiast community and ever since I was young, I always wanted to do car-related work.

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