AutoCodes – Nissan – P0304 2008 Nissan Maxima

P0304 2008 Nissan Maxima Code - Number 4 Cylinder Misfire Detected

Quick Answer

When a misfire occurs, engine speed will fluctuate. Common causes include Faulty Spark Plug #4, Clogged or faulty Fuel Injector #4, Faulty Ignition Coil #4. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P0304 2008 Nissan Maxima indicates Number 4 Cylinder Misfire Detected.
Common causes: Common causes include Faulty Spark Plug #4, Clogged or faulty Fuel Injector #4, Faulty Ignition Coil #4.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

Save to My Repairs Step-by-Step Diagnostic Guide My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 4,660

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Mar 29, 2024

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P0304 2008 Nissan Maxima Description

When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring. The Diagnostic Trouble Code (DTC) will be set when the Engine Control Module monitors the crankshaft speed and has detected that engine cylinder #4 is misfiring.

OBDII Code P0304 2008 Nissan Maxima - Number 4 Cylinder Misfire Detected - AutoCodes.com — P0304 2008 Nissan Maxima Code - Number 4 Cylinder Misfire Detected

What does this mean?

What are the Possible Causes of the DTC P0304 2008 Nissan Maxima?

Faulty Spark Plug #4
Clogged or faulty Fuel Injector #4
Faulty Ignition Coil #4
Fuel Injector #4 harness is open or shorted
Fuel Injector #4 circuit poor electrical connection
Ignition Coil #4 harness is open or shorted
Ignition Coil #4 circuit poor electrical connection
Insufficient cylinder 4 compression
Incorrect fuel pressure
Intake air leak

How to Fix the DTC P0304 2008 Nissan Maxima?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What does this mean?

Code Tech Notes

The P0304 code means that cylinder #4 is misfiring or is randomly misfiring. Start by checking for intake leaks and if no leaks are found the next step is to replace the spark plugs on cylinder #4. If the problem persists more tests need to be done to diagnose the problem. See "Possible Causes" for the most common problems.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0304 2008 Nissan Maxima code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P0304 2008 Nissan Maxima code?

Need more information on how to fix the P0304 2008 Nissan Maxima code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0304 2008 Nissan Maxima code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0304 2008 Nissan Maxima Code

What does the OBDII code P0304 indicate on a 2008 Nissan Maxima?

The code P0304 indicates that a misfire has been detected in the number 4 cylinder of the engine. This can affect engine performance and should be addressed promptly.

What are common symptoms of a cylinder misfire in a 2008 Nissan Maxima?

Symptoms of a cylinder misfire (P0304) include rough idling, engine vibration, decreased fuel efficiency, the engine sounding unusually noisy, and the check engine light turning on.

What might cause the P0304 code in a 2008 Nissan Maxima?

Possible causes of a P0304 code include faulty or worn spark plugs, damaged spark plug wires or coils, issues with the fuel injector, or low compression in cylinder 4.

How can I fix the P0304 code in my 2008 Nissan Maxima?

To fix a P0304 code, start by inspecting and, if necessary, replacing the spark plugs and wires. Also, check the ignition coil and the fuel injector for damage or malfunction. If these parts are in good condition, further diagnosis may be required to check for engine mechanical issues.

Is it safe to drive a 2008 Nissan Maxima with a P0304 code?

Driving with a misfire (P0304) can lead to engine damage or poor performance. It is advisable to address the issue as soon as possible to avoid potential costly repairs.

Can a P0304 code affect the fuel economy of a 2008 Nissan Maxima?

Yes, a misfire in one of the cylinders, such as indicated by the P0304 code, can cause the engine to consume more fuel and decrease its efficiency, leading to worsened fuel economy.

What tools are needed to diagnose the P0304 code on a 2008 Nissan Maxima?

To diagnose the P0304 code, you will typically need an OBD-II scanner to read the code and monitor engine data, a multimeter for electrical tests, and possibly a compression tester to check for engine mechanical issues.

How do I prevent future cylinder misfires in my 2008 Nissan Maxima?

Regular maintenance is key to preventing misfires. This includes timely replacement of spark plugs and wires, keeping the fuel system clean, ensuring the ignition system is functioning properly, and regular checks for any diagnostic codes that may indicate developing issues.