When there is an issue with the car ignition, the first thing that comes to mind is the battery. And when there’s an ignition issue, you’re likely to face other issues such as engine misfire. This simply means that there are some issues with the combustion process in the cylinder.
But can a bad battery cause any misfire—combustion issues? In this article, we’ll dig deeper and find out the relationship between a bad battery and an engine misfire.
Can A Bad Battery Cause A Misfire?
A bad battery causes a misfire indirectly. The battery powers the fuel pump. The responsibility of the fuel pump is to pump the gas into the engine’s combustion chamber. And when the battery becomes weak, it affects the pump.
The fuel pump can slow down if the battery goes bad. As a result, the fuel becomes lean. Lean fuel means it contains more air than the fuel itself. If the fuel becomes too lean, then it will cause the engine to misfire.
Other parts of the engine are powered by the battery, such as the injectors. A bad battery can cause the injectors to open improperly. When injectors open improperly, a misfire is very likely to happen.
How To Inspect Cause of Engine Misfire
Keep in mind that the battery is not directly responsible for the engine misfire. Other reasons, like a damaged spark plug, malfunctioned sensors, etc., are more likely to cause a misfire. Here is how to prevent engine misfire.
- Check the spark plugs because damaged ones cause misfires most of the time.
- If the air and fuel mixture ratio gets altered, that can cause a misfire. It can cause by faulty emission systems, slow fuel pumps, malfunctioned injectors, etc.
- Issues with an internal circuit, like loose or damaged wiring, can cause it. So, check the internal circuit thoroughly.
- The best option is to use an OBDII code scanner. It will diagnose the car and show you the exact error codes. Then you can take action depending on the result.
How To Know About Your Battery Performance
The key to protecting your car from battery issues is always to monitor the battery performance. This helps you fix the problem before it could lead to engine misfiring. Here’s a chart of battery status and what each status means.
| Voltage | Charge Percentage | Battery Status |
| 12.6+ | 100% | Normal |
| 12.5 | 90% | |
| 12.4 | 80% | |
| 12.3 | 70% | Weak |
| 12.2 | 60% | |
| 12.1 | 50% | Slow Cranking |
| 11.9 | 40% | No Cranking |
| 11.8 | 30% | |
| 11.7 | 20% | |
| 11.6 | 10% | |
| 10.5 | 0% | Dead |
Weak Battery Symptoms
To protect your engine from battery-related misfiring, you should always identify battery issues early enough. Always check out for the following symptoms. These are signs that your battery is getting bad.
- The crank becomes slow
- The headlights get dimmed
- The battery terminals get corroded
- The battery loses the ability to hold a charge
- You might notice a smell coming from the battery.
Best Batteries To Buy for Your Car
Once you notice that your battery is bad, you need to replace it. However, you should at all times replace the battery with quality brands. Here are our top pics for the batteries that you should buy and replace your bad battery with.
- XS Power D3400 XS Series
- 12-volt battery
- Offers continuous high-power output due to its ultra-low resistance.
- It is an Absorbed Glass Mat battery.
- It is spill-proof,
- Vibration-resistant,
- sealed, and valve regulated.
- You can mount it in almost any position
Click here to check the latest price from Amazon.
- ACDelco Gold 48AGM
- It comes with a high-density negative paste, increasing battery life and improving performance.
- The use of Calcium Lead maximizes conductivity.
- The manufacturer included a vent cap with a design that resists acid leakage.
Click here to check the latest price on Amazon.
- ExpertPower
- The rugged construction of this battery
- Resistant to shock, heat, chemicals, and vibration.
- It is not only built for performance but also to last longer.
- It is spillproof and maintenance-free.
Click here to check the latest price on Amazon.
Frequently Asked Questions (FAQs):
- Can a bad battery cause rough idle?
The alternator will have difficulty keeping the engine running when the battery cannot put out enough power. So yes, a bad battery can cause a rough idle.
- What are the symptoms of a bad battery?
Among many symptoms, you should look for the slow crank, dim headlight, backfiring, and clicking sound when starting. These are the most common signs that your battery is failing.
- What are the common possible causes of a misfire?
The most common possible causes of misfires are ignition problems, fuel delivery problems, and problems with emission equipment.
- What sensors can cause a misfire?
If the airflow or the oxygen sensor fails, the engine can cause a misfire.
- What happens when a cylinder misfires?
When a misfire happens, you are likely to experience shaky or slow acceleration. Also, the engine could briefly lose power. When idle, you would notice more vibration than normal.
