However, if your vehicle hesitates or sputters during acceleration, it clearly indicates that something isn’t quite right. This problem can range from a sluggish response to intermittent jerking or misfires.
So, why does your car hesitate and sputter when accelerating? This issue can be attributed to problems with the fuel system, ignition system, air intake, exhaust, and sensor malfunctions. Some of the most common culprits are:
- A clogged air or dirty catalytic converter
- Dirty fuel injectors or clogged fuel filter
- Worn spark plugs or faulty ignition coil
- Malfunctioning MAF, MAP, or TPS
This article will provide insights into the specific reasons behind a car’s hesitation during acceleration. We will explore the symptoms that manifest and offer practical solutions to resolve them.
Why Does The Car Hesitate And Sputter When Accelerating?
Let’s explore why your car may exhibit this issue.
1.Fuel System Issues
The fuel system is the engine’s lifeblood. Any disruptions in this system can have a significant impact on your car’s ability to accelerate smoothly. Let’s look at two common culprits in the fuel system that can cause sputtering:
❖Clogged Fuel Filter
A clogged fuel filter impedes the flow of gasoline to the engine, diminishing the fuel supply necessary for proper combustion. When your fuel filter is clogged, you may experience engine sputtering, sluggish acceleration, and instances where your car stalls during rapid acceleration attempts.
Solution:
- Locate the fuel filter which is mostly situated along the fuel line between the fuel tank and the engine.
- Inspect the fuel filter for blockages and conduct fuel pressure tests. If the fuel pressure is abnormally low, it serves as a clear indicator of a clogged filter. The standard fuel pressure for carbureted engines should not be less than 4 psi. You can use an automotive fuel pressure tester to measure the pressure.
- To replace the fuel filter, use the appropriate wrench to detach the fuel lines from the filter.
- Install a new fuel filter in the same orientation as the old one. Reattach the fuel lines and tighten them securely.
❖Blocked Fuel Injectors
Fuel injectors are in charge of delivering a precise mist of fuel into the engine’s cylinders. When these injectors become clogged, the delicate balance of the fuel-air mixture is upset. This can impair engine performance.
Solution:
- Ensure your car’s engine is off.
- Find the fuel injectors that are usually located on the intake manifold.
- To access the injectors, you’ll need to remove the fuel rail. This typically involves disconnecting electrical connectors and fuel lines.
- Examine the fuel injectors for visible signs of blockage or buildup. If they appear clogged, it’s time for cleaning.
- There are specialized injector cleaning kits available. Attach the cleaning solution to the fuel rail and run the engine.
- Once the cleaning process is complete, reassemble the fuel rail.
If cleaning does not work, you need to get new fuel injectors.
2.Ignition System Problems
The ignition system generates the sparks needed to ignite the air-fuel mixture in the engine’s cylinders. Engine sputtering occurs when this system encounters difficulties that result in irregular combustion. The two most common causes here are:
❖Faulty Ignition Coil
The ignition coil transforms low-voltage electricity from your car’s battery into high-voltage sparks. When the ignition coil becomes faulty, it produces inconsistent sparks, resulting in engine misfires.
Solution:
- The ignition coil is situated near the engine and connected to spark plug wires.
- You can use a multimeter to look for any irregularities in the coil’s performance.
- To determine the extent of the variance, compare the multimeter results with those in the manual. Typically, the coil should produce between 0.7 and 1.7 ohms. In addition, visually inspect the coil for signs of damage.
- If damaged, replace the ignition coil.
❖Damaged Spark Plugs
If the spark plug is damaged, the car will hesitate and sputter when accelerating.
Solution:
- You may need to remove the engine cover or other components to access the spark plugs.
- Remove each spark plug using a spark plug socket. If they are damaged or excessively worn, it’s time for replacement.
- Using a spark plug gap tool, measure the spacing between the new spark plugs. Adjust the spacing as needed to meet the specs of your vehicle.
Carefully thread the new spark plugs into place by hand to avoid cross-threading. Then, use a torque wrench to tighten them to the manufacturer’s specifications.
3. Air Intake and Exhaust Issues
The air intake and exhaust system of your vehicle maintains a balanced flow of air and facilitates the removal of exhaust gasses. Blockages within this system will cause the car to sputter during acceleration. Let’s explore two prevalent issues within this system:
❖Clogged Air Filter
A clogged air filter restricts airflow to the engine. This, in turn, reduces combustion efficiency and causes reduced power and sluggish acceleration.
Solution:
- The air filter housing is found near the engine, often secured with clips or screws.
- Remove the air filter from its housing and examine it for signs of contamination, dirt, or clogging. If it’s dirty or clogged, replace it.
- Install a new air filter into the housing, ensuring it is oriented correctly. Close the housing and secure it with clips or screws.
❖Dirty Catalytic Converter
When a blockage occurs within the catalytic converter, exhaust gasses from the combustion chamber can be forced back into it. This disrupts the generation of new combustion, resulting in engine sputtering.
If a catalytic converter is clogged, your exhaust will remove colored smoke or emit a rotten egg odor.
Solution:
- In case of minor blockages, a dirty catalytic converter can be cleaned using a specialized catalytic converter cleaner.
If the catalytic converter is severely clogged or damaged, it needs to be replaced. This procedure is pretty complicated and is best left to professional mechanics.
4. Sensor Issues
Sensors are the observers of your car’s engine performance. They constantly send critical data to the engine control unit (ECU). The main sensors that can cause the car to sputter are the MAP, MAF, and throttle position sensors. Let’s take a look at each one and how to deal with it:
❖Damaged Mass Airflow (MAF) Sensor
The mass airflow sensor measures the amount of air entering the engine. When the MAF sensor is damaged, it can provide incorrect airflow data to the ECU. This leads to poor fuel-air mixture, hence hesitation.
Solution:
- Use an OBD-II scanner to check for the error code related to the MAF sensor. This code is usually P0101. Additionally, visually inspect the sensor.
- If found to be a fault, replace the MAF.
- Carefully disconnect the electrical connector attached to it.
- Remove screws or clamps holding the MAF sensor in place and take it out.
- Place the new MAF sensor and reattach any screws or clamps as necessary.
- Reconnect the electrical connector to the MAF sensor.
❖Manifold Absolute Pressure (MAP) Sensor Issues
The Manifold Absolute Pressure sensor measures the pressure in the intake manifold. Faults in the MAP sensor can result in incorrect pressure readings, affecting engine performance.
Solution:
- Check for trouble codes related to the MAP sensor, just as you did with the MAF sensor. P0106 will be the code that appears.
- MAP sensors are typically found on or near the intake manifold. To replace the MAP sensor, repeat the steps outlined in the MAF replacement section.
❖Throttle Position Sensor (TPS) Problems
The Throttle Position Sensor monitors the position of the throttle plate in the intake manifold. It helps in determining the appropriate fuel injection and ignition timing.
- Use an OBD-II diagnostic scanner to check for error codes. The TPS-related code is P0122.
- You can also use a multimeter to check the sensor’s voltage output. The voltage should increase or decrease smoothly and consistently. Any erratic readings indicate a faulty TPS sensor.
- If found damaged, replace the TPS Sensor. It is essential to consult a professional mechanic for this procedure, as proper calibration is required.
Here is a video elaborating on the causes of car sputtering we have discussed above.
FAQs
Here are some relevant questions people also ask about the car hesitation and sputtering while accelerating.
Q1. What can I do to prevent my car from hesitating and sputtering during acceleration?
Regular maintenance is critical. Follow the manufacturer’s recommended service schedule, which includes changing air filters, spark plugs, and fuel filters at the recommended intervals.
Q2. Is it safe to drive my car when it hesitates during acceleration?
You can still drive even when your car sputters. However, it can potentially cause damage to the engine and other components. Therefore, it’s best to have the issue diagnosed and repaired as soon as possible to avoid more costly repairs down the road.
Q3. Can a vacuum leak cause a car to sputter?
Yes, a vacuum leak can cause a car to sputter. A vacuum leak disrupts the balance of air and fuel in the engine. This leads to poor combustion and engine misfires, which can result in sputtering during acceleration.
Conclusion
It is undoubtedly frustrating to experience hesitation and sputtering when accelerating. Simple problems like clogged air filters or malfunctioning fuel filters are simple and inexpensive to repair. However, ignoring these minor issues may eventually lead to much more expensive repairs. You can effectively address these issues now that you are informed about the potential causes and solutions. Remember that regular maintenance and timely diagnosis are critical to keeping your car running smoothly and ensuring a safe driving experience.