P0301: Cylinder 1 Misfire Detected
A generic powertrain (engine and transmission) trouble code, same meaning on every brand.
Minimize driving; a flashing check engine light means stop - persistent single-cylinder misfire dumps raw fuel into the exhaust.
Symptoms
- Steady shake at idle (one cylinder dead or weak)
- Loss of power, flashing light under load
Likely causes, most common first
- Spark plug or coil on cylinder 1 (swap test settles it fast)
- Injector on cylinder 1 clogged or dead
- Low compression in cylinder 1 - valve or ring trouble
Read P0301 yourself before paying for diagnosis
A basic Bluetooth OBD-II scanner ($20-40) plugs into the port under the dashboard and shows this code with live sensor data on your phone - useful both for confirming the fix and for talking to a shop from an informed position.
What is going on and how it gets diagnosed
P0301 is a misfire isolated to cylinder 1 - unlike P0300's scatter, this points at one cylinder's ignition, fuel, or mechanical health. That specificity is diagnostic gold: swap the coil (or plug) with a neighboring cylinder and see whether the code follows the part.
If ignition and injector check out, a compression or leak-down test on that cylinder is the moment of truth. Sibling codes P0302 through P0308 mean the same fault logic applied to their respective cylinders - the diagnosis playbook is identical, only the cylinder number changes.
Repair options and cost
Typical US independent-shop ranges, parts and labor. Dealers run higher; regional labor rates vary.
Owner reports mentioning P0301
“just got on the freeway when car lost power, slowed down, check engine light turns on, and more lights start flashing. Potentially could have caused an accident if I was going faster on road. Went to mechanic, Code P0301, after diagnosis, fuel injectors failing. Mechanic was able to reproduce incident. Similar to recall for previous models, but not recalled on 2022 model. Need to replace fuel injectors. Had minor loss of power a few days prior, but not as severe”2022 Honda Ridgeline · Sep 2026
“The engine light on my 2017 Ford Escape EcoBoost 2.0L has come on a couple times in the last few months. My trusted mechanic has diagnosed the following codes: P0301 and P0316 - which indicates cylinder misfire and misfire detected on start up. There is an active TSB 22-2226 (Coolant intrusion into Spark Plug/Cylinder Bore) that matches up with those codes. This is my daughter's primary vehicle and we are not comfortable with her continuing to drive it for fear of total engine lockup. I took it into my local dealership to have them do their own diagnosis and to contact Ford corporate to determine the appropriate path to resolution. Current mileage is approximately 72,700 miles.”2017 Ford Escape · Sep 2026
“Cylinder misfire (e.g., Code P0301-P0304) Low coolant levels with no visible leaks Rough idle/shaking on startup Check engine light”2017 Ford Edge · Sep 2026
Show 7 more owner reports
“The contact owns a 2016 Ford Edge. The contact stated that coolant was entering the engine combustion chamber. The check engine light was illuminated, and the vehicle displayed DTC: P0301. The contact also referenced a scanner displaying code 4301. The contact stated that there was a sweet smell while starting the vehicle, which was consistent with coolant intrusion into the engine. The condition progressively worsened. The contact consulted with an independent mechanic. The contact was concerned that the vehicle might stall or that the engine could suffer catastrophic damage while driving on the highway. The failure mileage was approximately 83,000.”2016 Ford Edge · Sep 2026 · 83,000 mi
“Head gasket blew, and car overheated immediately on the freeway, with no warning signs, and at only 43,000 miles when a failure like this should not occur. Had to find a place to pull over and be towed to avoid more engine damage. Both independent mechanic and Ford dealership has confirmed this. Official diagnosis is "Remove and replace cylinder head assembly and replace head gasket - coolant intrusion cylinder 1, P0316, P0301." Apparently it's a known issue with this particular engine and has a pending lawsuit.”2019 Ford Mustang · Aug 2026
“Check engine light on. Codes P0316, P0300, P0301, P0302. Technician confirmed via scope coolant intrusion on cylinder 1 and 2. Technician stated it is known issue with this engine and recommends a new engine for $16,169.92. This has been an ongoing issue for the past two years.”2017 Lincoln MKC · Aug 2026
“vehicle may experience driveability issues, which may result in DTCs P0300 (random misfire detected), P0301 (No. 1 cylinder misfire detected), P0302 (No. 2 cylinder misfire detected), P0303 (No. 3 cylinder misfire detected), P0304 (No. 4 cylinder misfire detected), or P0172 (fuel system too rich) or a whirling noise coming from the engine compartment. POSSIBLE CAUSE Based on certain driving patterns and environmental factors, the DTC's stated above may be set or a whirling noise may occur. Apparently only certain vin numbers were affected, mine is not in the list but im still having the exact same issues.”2017 Honda CR-V · Aug 2026
“Car overheated and losing coolant. I just purchased this car on 6/22/2026 and having issues already. The check engine light is on and giving a p0301 code. I'm having to add coolant everyday to keep the car from running hot.”2018 Ford Escape · Jul 2026
“I own a 2020 Ford Mustang EcoBoost with approximately 75,000 miles. My vehicle developed a check engine light with diagnostic codes P0300 (random misfire) and P0301 (cylinder 1 misfire). I also began experiencing white smoke from the exhaust during cold starts. An independent repair shop suspects coolant is entering cylinder 1 due to a possible head gasket failure. They have recommended removing the cylinder head to inspect for cracks, check for warping, pressure test the head, inspect the cylinder walls, and replace the head gasket and related components if no further engine damage is found. The vehicle was properly maintained, and these symptoms appeared unexpectedly.”2020 Ford Mustang · Jul 2026
“For a couple months, repeatedly getting various cylinder misfire error codes: P0300, P0301, P0302. The engine stutters on startup and sometimes at idle. Coolant level drops gradually day-to-day. No visible leaks from hoses, radiator, or heater core. Suspect it may be leaking into cylinders. Replaced all four spark plugs, but problem continued to occur a couple days later. Have not yet confirmed with service center where coolant leak is occurring.”2018 Ford Edge · Jul 2026
Cars that report P0301 most often
Based on mentions of this code in NHTSA owner complaints.
P0301 by make
Makes with enough NHTSA reports of P0301 for a page of their own - which models and years report it.
Frequently asked questions
Can I drive with P0301?
Minimize driving; a flashing check engine light means stop - persistent single-cylinder misfire dumps raw fuel into the exhaust.
How much does it cost to fix P0301?
Typical US repair costs range from $80 for the simplest fix (spark plug(s)) to $5,000 in the worst case. The right number depends on which cause your car has - see the causes list.
Related codes
The codes closest to P0301. They often appear together, and telling them apart is usually what narrows the diagnosis.
Definition per SAE J2012 standard nomenclature. Symptoms, causes and costs are editorial guidance - always confirm with a diagnosis of your specific vehicle.