P0301 Code: Cylinder 1 Misfire and the Next Diagnostic Steps
Contents
P0301 identifies a cylinder 1 misfire. Confirm the engine’s cylinder layout and diagnostic evidence before replacing a coil, plug or injector.
OBD-II P0301 overview with a specifically scoped 2013–2017 Honda Odyssey example. Cylinder numbering and repair tests depend on the engine.
A flashing engine warning can indicate a damaging misfire. Follow the vehicle manual; stop safely and seek assistance for severe shaking, loss of power or unsafe operation.
Cylinder 1 is the location, not the repair
P0301 reports a misfire assigned to cylinder 1. It does not identify the cause or tell you which physical corner of the engine contains that cylinder. Use the engine-specific cylinder diagram.
A broader P0300 misfire warning carries different location information. Keep all codes from the same scan instead of dropping those that seem less specific.
A useful example from Honda
Honda bulletin 26-001 covers eligible 2013–2017 Odyssey vehicles with specified misfire codes. It describes oil-related spark-plug fouling and requires diagnosis; its inspection path does not apply when the relevant plug is not fouled.
That is a model-specific reason not to equate P0301 with a failed ignition coil. It is also not evidence that another vehicle has piston-ring trouble. Eligibility and current instructions need a VIN check.
Describe when the engine runs badly
Note whether the symptom occurs during a cold start, warm idle or acceleration, and whether the warning is steady or flashing. Keep recent repair details and the complete scan report.
Ask the workshop which observation or test confirms the fault in cylinder 1. A recommendation to replace a part should be tied to that evidence, not merely to the cylinder number.
Treat the warning lamp as part of the information
Ford’s warning-lamp guidance notes that flashing can accompany misfire and damaging exhaust temperatures. Your own manual provides the response for your vehicle.
Do not keep driving to reproduce severe shaking or loss of power. Request a repair-verification result after the cause has been addressed rather than treating an erased code as the entire outcome.
Frequently asked questions
Does P0301 always mean the coil is faulty?
No. It identifies the cylinder where misfire was detected, not the failed component.
Is cylinder 1 always closest to the front bumper?
Do not assume that. Use the cylinder-location diagram for the exact engine.
Does the Honda bulletin apply to every Odyssey?
Its listed years and VIN eligibility must be checked, and its diagnostic conditions must be satisfied.
Check the original documents
Sources
- Honda bulletin, cylinder-specific misfire diagnosis, pages 1 and 10
P0301 cylinder 1 and specific oil-fouling diagnosis
- Ford owner manual: Malfunction Indicator Lamp
Flashing lamp, misfire and catalyst damage risk
Sources checked on 2026-10-07. Follow the instructions for your exact model.
