P0304 Infiniti Code - Number 4 Cylinder Misfire Detected
Quick Answer
The P0304 Infiniti code indicates that there is a misfire detected in the number 4 cylinder of the engine. Common causes include Faulty spark plug in the number 4 cylinder, Failing ignition coil, Clogged fuel injector. 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 Infiniti indicates Number 4 Cylinder Misfire Detected.
- Common causes
- Common causes include Faulty spark plug in the number 4 cylinder, Failing ignition coil, Clogged fuel injector.
- 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.
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Code P0304 Infiniti Description
The P0304 Infiniti code indicates that there is a misfire detected in the number 4 cylinder of the engine. A misfire occurs when there is a lack of combustion in the cylinder, which can lead to a rough idle, decreased fuel efficiency, and potential damage to the catalytic converter over time. The misfire can be caused by various factors, such as a lack of spark, fuel, or compression in the cylinder.
Common Causes of P0304 Infiniti
- Faulty spark plug in the number 4 cylinder
- Failing ignition coil
- Clogged fuel injector
- Vacuum leak in the intake manifold
- Low compression in the number 4 cylinder
Symptoms of P0304 Infiniti
- Rough idle or vibrations while driving
- Decreased fuel efficiency
- Loss of power during acceleration
- Engine misfires or hesitation
- Check engine light illuminated on the dashboard
How to Fix P0304 Infiniti
- Perform a visual inspection of the spark plug and ignition coil in the number 4 cylinder to check for any signs of wear or damage. Replace if necessary.
- Use a scan tool to check for any stored trouble codes and monitor live data to pinpoint the exact cause of the misfire.
- Test the fuel injector in the number 4 cylinder to ensure it is functioning properly. Clean or replace as needed.
- Check for any vacuum leaks in the intake manifold that may be causing a lean condition in the number 4 cylinder. Repair or replace any damaged components.
- Perform a compression test on the number 4 cylinder to verify that it is within the manufacturer's specifications. Address any low compression issues accordingly.
Cost to Fix P0304 Infiniti
The typical repair costs for addressing a P0304 Infiniti code can vary depending on the specific cause of the misfire. On average, parts such as spark plugs, ignition coils, and fuel injectors can range from $50 to $200 each. Labor costs can add an additional $100 to $300 or more, depending on the shop's hourly rates and the complexity of the repair. In total, the repair for a number 4 cylinder misfire could range from $200 to $800 or more. It's recommended to consult with a qualified mechanic for a more accurate estimate based on your vehicle's make and model.
Tech Notes for P0304 Infiniti
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Information for Specific Infiniti Models
- P0304 2003 Infiniti G35 — Number 4 Cylinder Misfire Detected
- P0304 2004 Infiniti G35 — Number 4 Cylinder Misfire Detected
- P0304 2005 Infiniti G35 — Number 4 Cylinder Misfire Detected
- P0304 2006 Infiniti G35 — Number 4 Cylinder Misfire Detected
Frequently Asked Questions about P0304 Infiniti Code
What does OBD-II code P0304 mean for an Infiniti?
Code P0304 indicates a misfire in cylinder number 4, meaning the engine isn't firing properly in that specific cylinder.
What are common symptoms of a P0304 code?
Symptoms include rough engine idling, decreased fuel efficiency, difficulty starting the engine, and the Check Engine Light turning on.
What can cause a P0304 code in an Infiniti?
Common causes include a faulty spark plug, bad ignition coil, clogged fuel injector, vacuum leak, or low cylinder compression.
Can driving with a P0304 code damage my Infiniti?
Yes, driving with a misfire can cause further engine damage and harm the catalytic converter due to unburned fuel entering the exhaust system.
How do you diagnose a P0304 code in an Infiniti?
Diagnosis involves checking the spark plug, ignition coil, fuel injector, and cylinder compression, as well as inspecting for vacuum leaks or wiring issues.
What are the repair options for a P0304 code?
Repairs may include replacing the spark plug or ignition coil, cleaning or replacing the fuel injector, fixing vacuum leaks, or addressing low cylinder compression.
Can a dirty fuel injector cause a P0304 code?
Yes, a clogged or malfunctioning fuel injector can disrupt fuel delivery to cylinder 4, leading to a misfire.
How much does it cost to fix a P0304 code in an Infiniti?
The cost varies depending on the cause, but replacing a spark plug or ignition coil may cost $100-$300, while more complex repairs like resolving compression issues could be significantly higher.
Can bad fuel cause a P0304 code?
Yes, contaminated or low-quality fuel can lead to improper combustion and contribute to cylinder misfires.
Should I reset the P0304 code after repairs?
Yes, after completing repairs, use an OBD-II scanner to clear the code and ensure the issue has been resolved.
Discuss the causes and fixes for P0304 Infiniti OBDII Code
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I have a 97 q45 and changed all the plugs , diagnostic says misfire on 1. Took all back apart and changed plug again. Car seems to run well until get speed up. then it shakes somewhat... any ideas
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More than likely you have a problem with the ignition coil. You should try swapping the coil #4 with the #6. If after swapping the coil you get the P0306 code, then the problem is the coil you installed on the cylinder #6.
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hay i have a 04 Infinity FX35 with a po304 code, Ive changed the sparkplug as well as the coil. But i still get the code PO304. Ive even changed coil 2 to 4 and still get code PO304
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Although is not common, the next step is to check or change the fuel injector. If the injector check OK, the next step is to perform a compression test. The ignition coil is probably the most common problem, make sure the connector is fully connected.
When did the problem started?
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