P0301: Cylinder 1 Misfire Detected
Can you still drive? Not recommended if the check engine light is flashing. A flashing light indicates severe misfires that can damage the catalytic converter.
What Does P0301 Mean?
Code P0301 indicates that the engine control module has detected a misfire specifically in cylinder 1. A misfire occurs when the air-fuel mixture in the cylinder fails to ignite properly. The ECM detects this by monitoring crankshaft speed variations. Cylinder-specific misfires are generally easier to diagnose than random misfires because the problem is isolated to one cylinder.
Need to read your codes?
An OBD-II scanner lets you read and clear diagnostic trouble codes from your vehicle's computer. Most scanners work with any car made after 1996.
Browse OBD-II Scanners on AmazonCommon Causes
- Worn spark plug in cylinder 1
- Failed ignition coil for cylinder 1
- Clogged or leaking fuel injector
- Low compression in cylinder 1
- Vacuum leak near cylinder 1 intake runner
Symptoms
- Check engine light flashing
- Rough idle
- Loss of power
- Engine vibration
- Increased fuel consumption
Diagnostic Steps
- 1Swap ignition coil from cylinder 1 to another cylinder and check if misfire follows
- 2Inspect and replace spark plug in cylinder 1
- 3Test fuel injector operation with noid light
- 4Perform compression test on cylinder 1
- 5Check for vacuum leaks near cylinder 1
- 6Inspect valve train for cylinder 1
Recommended Parts & Tools
Estimated Repair Cost
| Type | Estimated Cost |
|---|---|
| Total Repair Cost Range | $50 - $1200 |
| Parts Only (DIY) | $50 - $200 |
| Labor (1-3 hrs @ $100/hr) | $100 - $300 |
Get a Personalized AI Diagnostic Report
Get a detailed AI diagnosis for code P0301 specific to your vehicle. Includes step-by-step repair instructions, exact parts needed, and a cost breakdown tailored to your make and model.
Chat with AI About P0301Commonly Affected Vehicles
Related Recalls
1 Active Recall — 2026 Ford F-150
The following NHTSA safety recalls have been issued for this vehicle. Contact your dealer to check if your vehicle is affected.
ELECTRICAL SYSTEM: INTEGRATED TRAILER BRAKE CONTROL
Ford Motor Company (Ford) is recalling certain 2021-2026 F-150, 2022-2026 F-250 SD, F-350 SD, F-450 SD, F-550 SD, Maverick, 2024-2026 Ranger, 2023-2026 F-600 SD, 2022-2027 Lincoln Navigator, Expedition, and 2026 E-Transit vehicles. When towing a trailer, the integrated trailer module (ITRM) may lose communication with the vehicle, possibly causing a loss of brake and turn signal lights, or a loss of brake function. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 108, " Lamps, Reflective Devices, and Associated Equipment."
Remedy: The integrated trailer module software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. Owner notification letters are expected to be mailed March 17, 2026. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 26C10. Vehicle Identification Numbers (VINs) involved in this recall will be searchable on NHTSA.gov beginning March 17, 2026.
Data provided by the National Highway Traffic Safety Administration (NHTSA).
Frequently Asked Questions
How do I know which cylinder is number 1?
Cylinder 1 location varies by engine. Check your owner's manual or look for cylinder numbers stamped on the intake manifold or coil packs.
Can I swap coils to diagnose a misfire?
Yes, swapping the coil from cylinder 1 to another cylinder is an excellent diagnostic technique. If the misfire moves to the new cylinder, the coil is bad.
Community Fix Reports
Community reports are user-submitted and not verified by Auto AI Buddy. Results may vary.
Related Codes
Affiliate Disclosure: This page contains affiliate links. If you purchase products through these links, we may earn a small commission at no additional cost to you. This helps us maintain this free resource. We only recommend products we believe will help you diagnose and repair your vehicle. Prices shown are estimates and may vary.