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First of all, what is misfiring? Misfiring is when one of the cylinders of your engine somehow
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doesn't fire when it should. So it gets the fuel, but it doesn't fire because it doesn't have the
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spark, because it doesn't have the compression, or because of some other reason, but it doesn't
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fire. So how can you understand that the engine is misfiring? You will need to spot several of
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the symptoms that I will tell you about today. And the first symptom, which is pretty common sense,
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is the loss of power. So when one of the cylinders misfires several times, you basically have not a
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four-cylinder engine but a three-cylinder engine. So one cylinder just doesn't produce any power,
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and this causes power loss, of course. But the power loss in this case will be only at
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the moment when you have misfiring. So when your engine works, like, for example, you give a lot of
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RPMs to your engine, and it works just okay, so in this case, you will not have the power loss. But
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when the misfiring occurs, the power will be much lower. The second thing you want to pay attention
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to is hesitation. So when you press the gas pedal, but your engine hesitates and doesn't want to
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accelerate immediately, this is one of the common things that misfiring causes. One of the cylinders
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will just skip the moment when it should fire, and you don't have the power to accelerate. So your
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engine may even stall at this moment, but this happens only when several cylinders misfire, so
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there is a huge problem with the engine. Then, if you experience sudden vibrations in your engine,
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this is also the sign that shows misfiring. Why? Because when your engine, for example, it's a
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four-cylinder engine, and suddenly it becomes a three-cylinder engine, it comes out of balance,
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so it starts vibrating. But this vibration is not constant, so your engine doesn't vibrate
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constantly; it vibrates only when the misfiring occurs. So when one of the cylinders misfires,
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your engine becomes shaky, and you will feel this on the entire body of your car, and you
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will see this when you open the hood and look at the engine. You will see that it shudders a
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little bit from time to time. This is a very clear symptom of misfiring. Then, sometimes you may have
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black exhaust. This doesn't occur at all times because sometimes the misfiring is not that bad,
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and all this fuel that comes through the engine without being burned there, it will be burned in
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the catalytic converter, and you will not have the huge amount of black exhaust. But sometimes,
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sometimes it may happen when the misfiring is really bad, and a lot of fuel isn't burnt. But
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because what happens when the engine misfires is your injector will still inject some fuel
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into the cylinder, but the cylinder will not burn this fuel, and part of this fuel will go inside
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the engine, down the engine, so it will dilute the oil, which is not good at all. But part of
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this fuel will go to the exhaust system when the valves, when the exhaust valves open, part of this
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fuel will go to the exhaust system, and then it will burn directly in the exhaust system, in the
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catalytic converter, in some other tubes and parts of the system, which is pretty bad because it will
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raise the temperature in the catalytic converter, and it will destroy the catalytic converter if you
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ignore this problem. So when you actually have black smoke from the tailpipe, and you suspect
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that it's because of misfiring, you need to take action. You need to repair the engine; otherwise,
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it's going to cost you much more in several weeks. And the fifth symptom, which is pretty easy to
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spot if you have a scanner, it's the code P300 or P300N (some number). When you have the code P3000,
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it means several cylinders misfire. They may misfire all together or one by one,
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but if you get P3000, it means that the problem is not likely with one of the spark plugs or one
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of the ignition coils. The problem is with something else, like engine electronics or
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maybe the compression or maybe something like that. But when you get the trouble code P0301,
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you are sure that this is about the first cylinder. So the misfiring occurs in the
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first cylinder. P0302 will tell you about the second cylinder, P0303 about the third cylinder,
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and so on and so forth. And you may also see some other codes for the exhaust system problems,
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etc. So if you have the scanner, check it, and you will see easily that this is misfiring.
