You’re driving along in your car when it starts to lose power and vibrate. What’s going on?
These are some of the biggest signs that your car could be suffering from a misfiring cylinder. In order to understand what this means, it’s good to first know a bit about your car’s cylinders.
What is a cylinder? This is the engine component where combustion occurs so it basically is responsible for giving your car power.
Your car could have between two and 12 cylinders depending on its type.
You don’t want to ignore a misfiring cylinder, but is it serious? Can you drive with it? Here’s everything you need to know.
What Does It Mean When Your Car Has A Misfiring Cylinder?
An engine cylinder is said to misfire when it can’t burn the air-fuel mixture that’s in the combustion chamber.
The engine will lose power and start to jerk a lot. This increases how much fuel your car consumes as well as its release of emissions.
It’s common for misfiring to occur when an engine component is damaged.
How To Tell If Your Car’s Cylinder Is Misfiring
Besides jerking movements, your car will show other signs of misfiring. These include symptoms such as stalling or vibrating; difficulty starting; and making popping sounds.
You can also diagnose misfiring by making use of a code reader or scan tool. This type of device will collect data from your vehicle’s computer to find out why it’s misfiring.
These tools can give you useful information, such as how many misfires have happened and the engine RPM when the misfires were noted.
What Causes A Misfiring Cylinder?
There are various problems that can cause your car’s cylinder to misfire. So, let’s dive into what could be causing it to happen to your vehicle.
- The air-fuel mixture isn’t correct. If there’s too much or too little air or fuel in your engine, this can cause it to battle to ignite. A failed fuel injector or vacuum leak are two things that can cause the air-fuel mixture in the car to get thwarted and cause problems.
- Internal engine problems can cause the cylinder to not be able to seal properly in order to create enough compression when the piston moves upwards to interact with the air-fuel mixture and create combustion. If the cylinder is not correctly sealed because of internal engine problems, this will result in not enough compression and the engine will misfire.
- There’s a loss of spark. This refers to anything that prevents the coil voltage from reaching the electrode gap on the spark plug, such as if the spark plug is dirty or damaged.
- Other parts of the ignition system are to blame. It’s not just sparking plugs that could be causing a misfiring cylinder – there are many other components in this system that could be to blame, such as the coil packs, wiring, and crankshaft position sensor.
- Another reason for a misfiring cylinder is if electrical circuits are not connected properly, such as if they are damaged or their wiring is loose. Since input and output engine components are usually connected with electrical circuits, such as in the case of sensors, a failure of them can cause the engine to misfire.
Idle Vs. Acceleration Engine Misfiring
As we’ve already seen in this article, a misfiring cylinder can be a complicated problem that requires a bit of investigation to understand why it’s happening.
An important thing to consider is if your cylinder is misfiring when you increase your vehicle speed or when it’s idle.
Let’s take a look at both of these situations in greater detail to get to the bottom of what’s happening.
If your engine misfires during acceleration
This is severely dangerous for the engine as well as other people on the road because your car might feel like it’s losing power when you accelerate. Your car might also jerk or vibrate.
A common cause for misfiring to happen when you accelerate your car is a damaged spark plug.
Since these plugs experience a lot of wear and tear, they can end up malfunctioning so that they can’t properly ignite the fuel in the piston cylinder.
There can be other reasons for misfiring during acceleration, such as faulty spark plug wires or a damaged distributor cap. It’s also common for a failing throttle position sensor to cause misfiring.
If this sensor isn’t working in the way that it should, it can throw off other systems in the engine, such as the fuel injection, because they need the throttle position sensor in order to work at their best.
If your engine misfires when the car is idle
You might feel confused about why your car is running well but experiencing misfiring when it’s idle.
This can be trickier to diagnose because this type of problem with your car won’t always provide a diagnostic code to enable you to get to the source of it.
This can also mean that mechanics sometimes won’t know what’s wrong, so they will have to undergo a bit of trial and error to solve the problem.
They might replace the fuel injectors, spark plugs, or fuel pump to try to fix what’s going on. A common cause for this type of misfiring, however, is an imbalance with the car’s air-fuel mixture.
This can be caused by various things, such as malfunctioning oxygen sensors or a vacuum leak.
How To Check Trouble Codes For A Misfiring Cylinder
If you have a car scanning device, it’s a good idea to try to figure out what cylinder is dealing with a misfire.
To properly understand what’s going on with your car’s cylinders, you will need to know what the diagnostic trouble codes are which point to a problem with these components. Here’s a rundown of popular trouble codes:
- P0100 – P0104: This means that there’s a problem with the mass airflow sensor
- P0171 – P0172: There’s an incorrect air-fuel mixture in the engine
- P0200: The fuel injector circuit is malfunctioning
- P0300: There’s a random misfire that is not isolated to one or two cylinders
The following are diagnostic trouble codes that point to specific cylinders which are not working properly:
- P0301: Cylinder 1
- P0302: Cylinder 2
- P0303: Cylinder 3
- P0304: Cylinder 4
- P0305: Cylinder 5
- P0306: Cylinder 6
- P0307: Cylinder 7
- P0308: Cylinder 8
How Long Can I Drive With A Misfiring Cylinder?
Although you might think that driving around with a misfiring car isn’t bad, it can be dangerous. Even if you manage to drive, the ride will be noisy and/or very uncomfortable, so it’s not worth it.
Your car will lose power, preventing you from being able to use it. You might find that the car aggressively jerks or loses power at crucial moments, which can be dangerous for you and people around you.
You could cause an accident because your car is not responding in the way that it should.
If you force your car to drive with a misfiring cylinder, this could damage the engine. If one cylinder is misfiring, this could cause a strain on other cylinders and cause them to malfunction.
Even if it seems like you’re not experiencing a lot of symptoms from a misfiring cylinder, such as if your car is only misfiring when idle, the best thing to do is take your car to a mechanic immediately so that the reason for the misfiring cylinder can be seen to and repaired.
This will prevent further problems from occurring, such as you being left stranded on a highway far away from home because your car refuses to go one more mile.
How Much Does It Cost To Repair A Misfiring Cylinder?
Now for the big question: how much does it cost to repair a misfiring cylinder? Since there are so many problems that could cause your car’s cylinder to misfire, the cost of repairing it can vary quite a bit.
For example, if you need to fix a faulty coil, this could cost around $300, and you’ll have to replace both the coil and the spark plugs.
If the problem is a bad fuel injector, you’re looking at between $200 and $500, while a vacuum leak or damaged piston rings can both set you back around $1,000 to $3,000.
You also have to bear in mind that the labor costs and materials required for the repair will vary depending on the city in which you live and the mechanic you enlist to repair the problem.
Do you have a malfunctioning carburetor?
A malfunctioning carburetor can cause similar symptoms to a misfiring cylinder, such as lower engine performance, but it will also cause the car to backfire or have difficulty starting.
Will a misfiring cylinder cause your “check engine” light come on?
If the car’s OBD2 system notes that there’s a misfire occurring, this will usually cause your “check engine” light to come on.
Having a misfiring cylinder can be stressful. It’s not safe to drive with it, so if you notice any symptoms of a misfiring cylinder you need to take your car to a mechanic as soon as possible so that you can get back on the road and prevent further damage to your car.