P0204 - Fuel Injector Circuit Malfunction (Cylinder 4) Common in 2008-2015 Honda Accord and 2009-2014 Toyota Camry

Quick Answer

P0204 means: P0204 indicates a malfunction in the fuel injector circuit for cylinder 4.

Fix: Check and replace faulty components Cost: $150 - $300 Time: 90-180 minutes

Can I drive with P0204? Immediate diagnosis and repair are recommended to prevent engine damage.

Common Questions

What does P0204 mean and how does it affect my car?

P0204 indicates a malfunction in the fuel injector circuit for cylinder 4, leading to possible engine misfires, reduced performance, and increased emissions. If left unaddressed, it can cause more significant engine damage.

What are the most common causes of P0204 and how much does it cost to fix?

Common causes include a faulty fuel injector (60% likelihood), electrical issues, or even a malfunctioning PCM. Repair costs can range from $150 for injector replacement to $200 for wiring repairs.

Can I drive my car with P0204 or should I stop immediately?

While it may be possible to drive short distances, it is not advisable as it can lead to further engine damage. Immediate diagnosis and repair are recommended.

How can I diagnose P0204 myself using the GeekOBD APP?

Use the GeekOBD APP to scan for trouble codes, check fuel injector function, and observe live data to see if cylinder 4 is receiving the correct fuel amount.

What vehicles are most commonly affected by P0204?

P0204 is frequently seen in vehicles like the 2008-2015 Honda Accord and the 2009-2014 Toyota Camry, often due to similar engine designs and fuel system components.

How can I prevent P0204 from happening again?

Regular maintenance, including fuel filter changes and injector cleanings, can help prevent issues. Keeping the engine clean and monitoring fuel quality are also beneficial.

What is P0204?

The diagnostic trouble code P0204 signifies an issue with the fuel injector circuit for cylinder 4. This code is crucial because it indicates that the powertrain control module (PCM) has detected a malfunction in the fuel injector circuit or the fuel injector itself for that specific cylinder. When this code appears, it often means that the injector is not opening or closing as it should, which can lead to poor engine performance, reduced fuel efficiency, and increased emissions. In practical terms, if the fuel injector fails to deliver the proper amount of fuel to cylinder 4, this can result in symptoms such as engine misfires, rough idling, and difficulty starting the vehicle. Vehicle owners may notice a decrease in acceleration and overall power, potentially leading to more extensive engine issues if not addressed promptly. Ignoring this code can lead to further complications, including damage to the catalytic converter and worsening fuel economy. Regular maintenance checks and timely repairs can help prevent these issues and keep your vehicle running smoothly.

System: P - Powertrain (Engine, Transmission, Emissions)

Symptoms

Common symptoms when P0204 is present:

  • Check engine light illuminates and stays on consistently, indicating a persistent issue with the fuel system.
  • Engine hesitates during acceleration, leading to a lack of power when attempting to speed up, which can be frustrating in traffic.
  • Fuel economy decreased by 10-15%, noticeable through increased frequency of visits to the gas station.
  • Rough idling occurs, with the engine vibrating noticeably at a stop, making it uncomfortable for passengers.
  • Difficulties starting the vehicle, especially after it has been sitting for a while, indicating potential fuel delivery problems.

Possible Causes

Most common causes of P0204 (ordered by frequency):

  1. The most common cause of P0204 is a faulty fuel injector for cylinder 4, with a likelihood of about 60%. This could be due to wear and tear or clogging that restricts fuel flow.
  2. Another possible cause is an electrical issue, such as damaged wiring or a poor connection in the fuel injector circuit. This typically occurs in older vehicles or those with rodent damage.
  3. A less common cause might be a malfunctioning PCM, which sends incorrect signals to the fuel injector. This is rarer but can happen after a software update or due to internal failure.
  4. A clogged fuel filter could also lead to insufficient fuel reaching the injector, although this is a less frequent trigger for this specific code.
  5. In rare cases, a vacuum leak could cause irregular air-fuel mixture ratios, affecting the injector's operation and subsequently triggering the P0204 code.

P0204 Repair Costs

Cost Breakdown by Repair Type

Fuel Injector Replacement

Replacing the faulty fuel injector for cylinder 4 to restore proper fuel delivery.

  • Total: $150 - $300
  • Success rate: 85%
Wiring Repair

Repairing or replacing damaged wiring in the injector circuit to ensure proper electrical flow.

  • Total: $100 - $200
  • Success rate: 90%
Money-Saving Tips for P0204
  • Start with the most common and least expensive repairs first
  • Use GeekOBD APP to confirm diagnosis before replacing expensive parts
  • Consider preventive maintenance to avoid future occurrences
  • Compare prices for OEM vs aftermarket parts based on your needs
  • Address the issue promptly to prevent more expensive secondary damage

Diagnostic Steps

Professional P0204 Diagnosis Process

Follow these systematic steps to accurately diagnose P0204. Each step builds on the previous one to ensure accurate diagnosis.

Step 1: Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion around the injector's connector (5-10 minutes)

Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion around the injector's connector (5-10 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 2: Step 2: OBD2 scan with the GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context; ensure you look for any related codes (10-15 minutes)

Step 2: OBD2 scan with the GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context; ensure you look for any related codes (10-15 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 3: Step 3: Component testing - Use a multimeter to check the injector's resistance and ensure it falls within manufacturer specifications; also test the circuit voltage to the injector (20-30 minutes)

Step 3: Component testing - Use a multimeter to check the injector's resistance and ensure it falls within manufacturer specifications; also test the circuit voltage to the injector (20-30 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 4: Step 4: System function test - After repairs, verify proper operation by observing injector activation with a scan tool and clearing codes (10-15 minutes)

Step 4: System function test - After repairs, verify proper operation by observing injector activation with a scan tool and clearing codes (10-15 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 5: Step 5: Road test verification - Drive the vehicle under various conditions to confirm the repair's effectiveness and ensure no additional codes have returned (15-20 minutes)

Step 5: Road test verification - Drive the vehicle under various conditions to confirm the repair's effectiveness and ensure no additional codes have returned (15-20 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.

Important Notes

  • Always verify the repair with GeekOBD APP after completing diagnostic steps
  • Clear codes and test drive to ensure the problem is resolved
  • Address underlying causes to prevent code recurrence

Real Repair Case Studies

Case Study 1: Fuel Injector Replacement on 2012 Honda Accord

Vehicle: 2012 Honda Accord, 75,000 miles

Problem: Customer reported engine misfires and decreased fuel efficiency.

Diagnosis: Using the GeekOBD APP, we confirmed P0204 and found the injector resistance was outside specifications.

Solution: Replaced the faulty fuel injector for cylinder 4 and cleared the error codes.

Cost: $250 (parts: $150 for the injector, $100 for labor)

Result: Post-repair, the vehicle ran smoothly with improved acceleration and fuel efficiency.

Case Study 2: Wiring Issue on 2010 Toyota Camry

Vehicle: 2010 Toyota Camry, 90,000 miles

Problem: Customer experienced rough idling and check engine light illuminated.

Diagnosis: The GeekOBD APP revealed P0204; inspection showed damaged wiring in the injector circuit.

Solution: Repaired the wiring and secured connections to restore proper injector function.

Cost: $180 (parts: $30 for connectors, $150 for labor)

Result: The vehicle's performance improved significantly, with no further codes appearing.

Diagnose P0204

Use GeekOBD APP for professional diagnosis!

  • Real-time data monitoring
  • Advanced diagnostic features
  • Step-by-step repair guidance
  • Professional-grade analysis
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Code Information

Code: P0204
System: Powertrain (Engine, Transmission, Emissions)
Severity: HIGH
Category: Engine Codes