Engine Misfiring – A Complete Guide

Whatever the cause, engine misfires need to be dealt with as soon as you can manage. Engine misfires can mess with your emissions, which could lead to a ticket. In addition, engine misfires can damage the other parts of your engine and lead to a bigger maintenance bill.

Engine Misfiring: What is It?

Engine misfiring is a common problem that can turn dangerous if left untreated. But these malfunctions often sound a lot worse than they actually are. Put simply, an engine misfire is a malfunction of the components needed for a cylinder to fire.

engine misfire

Sometimes this can be a result of incorrect ignition timing. Or it might be wear and tear on your valve spring or a vacuum leak. Other possible reasons include there not being oxygen for burning the fuel or a spark plug error.

Is Engine Misfiring Dangerous?

Driving with a misfiring engine can be dangerous for several reasons.

For starters, it can mess with your exhaust and turn it black. This is a hazard for both you and other drivers on the road.

Alternatively, engine misfires can cause you to lose power since they damage the other parts of the engine. Losing power while driving is incredibly dangerous as it takes control of your vehicle away. Furthermore, losing power may cause other parts of your engine to wear down quicker than normal.

There’s never a good time to drive with a misfiring engine. It’s recommended that you take your car into a mechanic to have your engine inspected right away. If you do need to drive your car to the auto shop, go slowly or consider hiring a towing company to make the trip for you.

How do You Know if Your Engine is Misfiring?

It’s not very hard to tell if your engine is misfiring. There are several major signals that you should pick up on as you drive your vehicle.

One of the biggest signs of a misfire is a loss of about 25% of your engine’s overall power. Basically, you won’t be able to drive as fast or as far if your engine is misfiring. This can also be accompanied by shaking or vibrations that you should feel in your steering wheel.

Misfiring engines may also be very difficult to start. Sometimes, this manifests as stalling whenever your car goes into an idle state, such as when you are waiting at a stoplight. If you have a cantankerous engine that doesn’t start consistently, it may be due to a misfire.

Of course, the telltale “bang” sound that accompanies many misfires is another surefire sign. While not all misfires have a gunshot-like sound accompany them, most do.

Finally, many modern vehicles’ “check engine” lights will come on when a misfire occurs. Keep an eye on this light your dashboard to stay abreast of any potential engine problems.

Read more: Car Engine: What It Is and How Does Car Engine Work?

How do you Fix a Misfiring Engine?

Thankfully, fixing a misfiring engine doesn’t have to be too complicated. You should always start with your “check engine” light and see what code it is displaying. Taking this code to an auto repair shop should allow you to pinpoint whether or not you are suffering from a real misfire.

Alternatively, you can buy a code reader and scan this information for yourself. It’s a good choice if you already have some auto mechanic experience. This tool can remove the code from the dashboard, as well.

You can perform the repairs you need yourself if you have some auto mechanical know-how already. You’ll need to check the various possible causes of your engine misfire.

Spark Plugs

Check the spark plugs first, as these are one of the most common causes. Because they’re so cheap, it’s often a good idea to swap them out to be sure they aren’t the problem. At the same time, you can replace the spark plug wires since they might be causing the misfire as well.

How to deal with engine misfiring

Vacuum Leaks

Next, pop opens the hood of your car and look for signs of a vacuum leak. Turn the engine on and listen for a high hissing noise. If you hear that, it’s a good sign that a vacuum leak is your issue.

To fix this, pinpoint the leak using a spray bottle filled with liquid dish soap. Spray the dish soap along both vacuum lines of your engine, as well as the manifold intake gasket. Don’t forget the PCV valve, too.

If you see bubbles, that’s where the crack or vacuum leak is. You can replace whatever damaged section you find.

Ignition Coil

Next, check your ignition coil, particularly if the engine misfire is accompanied by stalling or backfire sounds. This is most common on vehicles over a few decades old. Ignition coils are usually at the end of your spark plug wires.

Replacing your ignition coils shouldn’t be too expensive. The parts can be affordably purchased at most auto body shops. Be sure to pick out the correct ignition coil for your make and model of vehicle.

Mechanical Problems

Finally, you might be suffering from a mechanical misfire. You’ll have to check the major mechanical parts of your engine to ensure that everything is operating smoothly.

Examine the timing chain and make sure it hasn’t been stretched out too much from regular wear and tear. You can use a timing light while your engine is idling to see if your timing chain is stretched out. You’ll need to replace it if this is the case.

Check the intake manifold for a vacuum leak, as well. You can use the soapy spray bottle water technique that we described above to locate this leak if it exists.

Is a Misfiring Cylinder Expensive to Fix?

It depends on what work is needed to repair your engine. Many auto mechanic shops charge a flat fee for all misfiring cylinder jobs. Others will charge you for specific work or part replacements.

It’s often cheaper to make engine misfire repairs yourself if you can successfully identify the cause. However, make sure you know what you’re doing before attempting repairs. Making the problem worse could cost you more money in the long run.

Engine misfires repaired by auto mechanic shops run between $80 and $300 on average.

Foxwell NT530 Honest and Complete Review

5/5 (1 Review)

About The Author