If your car hesitates, jerks, or bucks when you accelerate, it usually means the engine isn’t receiving the right mix of fuel, air, or spark. This can make driving uncomfortable and unsafe, especially when merging or overtaking. Prompt inspection is important to prevent further engine or transmission damage.

What does it mean if a car hesitates or bucks?

Hesitation and bucking occur when the engine struggles to deliver smooth power. Instead of accelerating normally, the car may pause, lurch forward, or feel like it’s misfiring. This is often related to fuel delivery, ignition timing, or transmission faults.

Common causes of hesitation and bucking

• Dirty or clogged fuel injectors
• Failing fuel pump or blocked fuel filter
• Worn or fouled spark plugs
• Faulty ignition coils
• Mass airflow (MAF) or oxygen sensor issues
• Vacuum leaks in hoses or intake system
• Transmission problems (slipping or jerking)

Why do you need to fix this problem quickly?

Engine hesitation and bucking reduce performance and fuel efficiency. If ignored, these symptoms may worsen into full misfires, stalling, or transmission damage. Addressing the cause early prevents costly repairs and ensures safe, smooth driving.

How do you know when to get it checked?

Signs include:

• Jerking or lurching when accelerating
• Car hesitates or pauses before gaining speed
• Check Engine Light illuminated
• Unusual engine noises or vibrations
• Poor fuel economy

What happens during an assessment?

A mechanic will:

1. Scan the ECU for fault codes
2. Inspect spark plugs, ignition coils, and wiring
3. Check fuel pressure, injectors, and filter
4. Test sensors such as the MAF and oxygen sensor
5. Inspect transmission operation if symptoms occur during gear changes
6. Repair or replace faulty components as needed

How much does it cost to fix?

Costs depend on the cause. Spark plug or filter replacement may cost $150–$300. Injector cleaning or ignition coil replacement may cost $250–$600. Fuel pump or transmission repairs can range from $600–$2,500+.

Is it unsafe to drive with hesitation and bucking?

Yes. A car that hesitates or bucks can lose power unpredictably, making it dangerous in traffic or during overtaking. It should be inspected and repaired as soon as possible.