Purpose

This article outlines the procedures to diagnose and confirm Diagnostic Trouble Code (DTC) P0301 on a 2014-2019 Nissan Versa and to replace the Ignition Coil to resolve the issue.

Introduction

In cases where the Malfunction Indicator Lamp (MIL) on your vehicle’s dashboard is illuminated and the Engine Control Module (ECM) has stored DTC P0301 (Cylinder 1 Misfire Fault), it indicates the ECM has detected that the engine speed fluctuates through the Crankshaft Position Sensor (CKP) signal when the misfire occurs. A common cause of this DTC is the ignition coil.

The ignition coil plays a vital role in the efficient and reliable operation of an internal combustion engine. It acts as a transformer, converting the low voltage power from the battery into the high voltage required to create the spark needed to ignite the air/fuel mixture in the engine's combustion chamber.

To correct this issue, inspect the vehicle’s ignition system and replace the ignition coil as needed.

Symptoms of DTC P0301 include:

• Malfunction Indicator Lamp (MIL) ON or flashing
• Reduced engine power and performance
• Poor fuel economy
• Failed emission test

Possible causes of this fault are:

• Faulty or damaged spark plug
• Faulty or damaged fuel injector
• Vacuum leak

When DTC P0301 is present on a 2014-2019 Nissan Versa, replacing the ignition coil may resolve the issue.

(This image is for illustrative purposes only and may not match the actual part number)

Diagnostic Procedures:

Initial Inspection

During your initial inspection, check for obvious mechanical signs such as torn inlet boots, missing or broken vacuum tees and/or, cracked, broken, or disconnected wire harnesses. Inspect the ignition coil wire(s) or connector(s) to ensure they fit tightly on the spark plugs. Make sure the coil(s) and housing properly fit into the valve cover, cylinder head, and spark plug(s). In addition, check the ignition coil harness connector(s) for proper fitment into the connector(s) and holders. This will prevent short-to-voltage, short-to-ground, etc., or interference with other wires. With the engine idling, you may try spraying a fine mist of water across the wires and coil(s), looking for arcing and, or RPM change. In addition, inspect the battery terminals and check the state of charge before attempting to diagnose possible electrical faults. Refer to the Vehicle Emission Warranty Manual for time and mileage coverage for the emission-related fault(s). For additional information, refer to the Service Manual or applicable Technical Service Bulletin (TSB).

Diagnostic Procedures

1. Start and idle the engine. After the engine stalls, crank it two or three times to release all fuel pressure.

2. Turn the ignition switch OFF. Remove all ignition coil harness connectors to avoid electrical discharge from the ignition coils. Remove the ignition coil and spark plug of the cylinder to be checked.

3. Connect the spark plug and harness connector to the ignition coil. Fix the ignition coil using a rope etc., with a gap of 13–17 mm (0.52-0.66 in) between the edge of the spark plugs and the grounded metal portion, as shown in the figure. Crank the engine for about 3 seconds, and check whether a spark is generated between the spark plug and the grounded metal portion.

- If the spark is generated, the Ignition Coil is good. Inspect the other component as the Fuel Injector.

- If the spark is not generated, replace the Ignition Coil. Go to Step 3.

Repair Validation

1. Clear DTC(s) and Freeze Frame (FF) information.

2. Validate the repair by following the EVAP drive cycle requirements for the fault area.

3. Check for pending or stored DTCs. If none are found, the repair is complete.

Replace the ignition coil and spark plug

Removal

Step 1 – Disconnect the battery negative cable.

Step 2 – Remove the intake manifold.

Step 3 – Remove the ignition coil.

Install

Installation is accomplished in the reverse order of removal.

Repair Validation:

1. Clear DTC(s) and Freeze Frame (FF) data.

2. Perform perform the drive cycle requirements for the fault area.

3. Optionally, operate the vehicle within the conditions recorded in the Freeze Frame data when DTC P0301 was initially set.

4. Check for pending or stored DTCs. If none are found, the repair is complete.