Engine misfires can be quite jarring—if not a bit frightening.
A misfire is usually experienced as a lag in power delivery from your engine. It sometimes feels like your vehicle is “stumbling.” (Not to be confused with hard shifting.)
The good news about engine misfires is that while they can be indicative of an expensive problem, they usually aren’t. In today’s post we’ll be examining what causes engine misfires, how to diagnose the root cause, and how to prevent these jarring but not altogether uncommon symptoms.
Let’s begin by discussing what usually causes engine misfires, which will then tell us exactly where we need to look to prevent them from happening:
The Cause of Most Engine Misfires is Almost Always One of These Three Things
The cause of an engine misfire is almost always caused by:
- Problems with the fuel system, such as a clogged filter
- Mechanical problems, such as cracks in the vacuum lines
- Improper spark plug ignition
Of these issues, mechanical problems are likely to be the most serious. As we’ll learn in a moment, fuel filters and spark plugs are relatively easy and cheap to repair.
Before we move on, let’s talk about the importance of the check engine light. In most modern vehicles, it means that the onboard computer of your vehicle has detected a problem and has likely generated a diagnostic code. These diagnostic codes can be very specific, often capable of quickly and efficiently narrowing down the cause of the engine misfire.
If your check engine light is on, the best thing to do is visit your local BG certified automotive professional.
Identifying Ignition Problems Causing Engine Misfires
If the ignition system is the cause of your engine misfires, that’s not necessarily a bad thing—it’s likely to be an easy, affordable fix. Not only that, but these kinds of problems are to be expected from ignition parts, which wear down or become corroded through regular use.
Most commonly, the spark plug is the culprit. Due to wear and corrosion, the spark plug fails to perform. Oftentimes, it doesn’t simply stop working—it’s more of a gradual decrease in performance. So, you might experience small misfires at first which become worse and worse as time goes on. The good news? Spark plugs can be swapped out in just a few minutes.
When Engine Misfires are Caused By Common Fuel System Problems
When a misfire is being caused by a problem with the fuel system, by far and away the most common problem is a clogged fuel filter. Simply clean or replace the filter and the misfires should cease. Occasionally, the problem isn’t the fuel filter, but the fuel injectors. They can get dirty or accrue corrosion, which also causes engine misfires.
Finally, the EGR valve might also be the cause of the misfires. Over time it might start to stick, which results in exhaust entering the intake manifold. In these cases, the EGR valve must be replaced.
If you’d like to mitigate problems with your fuel system as much as possible, the easiest way to do so is with BG Platinum 44K Fuel System Cleaner, part of the fuel system service available at BG.
Mechanical Issues Possibly Responsible for Engine Misfiring
Mechanical issues tend to be less common than the other issues discussed here today, but can still occur and will cause engine misfires if left unchecked. Often the cause are cracks or leaks in the vacuum lines (which connect to the intake manifold). If discovered, these lines need to be replaced. While you or your mechanic are investigating under the hood, it’s a good idea to check the gaskets of the intake manifold as well, which can accrue corrosion as well.
Sometimes the mechanical problem isn’t as complicated to fix—if the timing belt has slipped or jumped, it can be realigned. If the belt has frays, replace it.
Learn More About the Value of Regular Automotive Maintenance With BG
Regular vehicle maintenance is the best way to extend the lifespan of your vehicle and ultimately save quite a bit of money in the long run. Here on the blog, we’ve discussed many common problems and their solutions. Just take a look:
- Loss of Power and Excessive Smoke? You Might Need a Dynamic Engine Restoration
- How to Maintain Your Power Steering System
- Do Engine Oil Supplements Like BG MOA Really Work?
Please feel free to contact us if you have any questions. We look forward to serving you!