Quick Answer
P0173 means: P0173 indicates a fuel trim problem in bank 2, affecting air-fuel mixture balance.
Can I drive with P0173? Address this issue promptly to prevent engine damage and reduced performance.
Common Questions
What does P0173 mean and how does it affect my car?
The P0173 code means there's a issue with the fuel trim on bank 2, which can lead to poor engine performance and increased emissions. If ignored, it may cause further damage to your vehicle.
What are the most common causes of P0173 and how much does it cost to fix?
Common causes include a faulty mass airflow sensor or vacuum leaks, with repair costs ranging from $100 to $600 depending on the issue.
Can I drive my car with P0173 or should I stop immediately?
While you may be able to drive your car, it's not advisable to ignore P0173. Doing so could lead to worse performance and potential engine damage. It's best to get it checked out as soon as possible.
How can I diagnose P0173 myself using GeekOBD APP?
Using the GeekOBD APP, you can scan for codes and review freeze frame data. Check the MAF readings and look for any irregularities that might indicate a fault.
What vehicles are most commonly affected by P0173?
Vehicles like the 2004-2008 Ford F-150 and 2006-2011 Honda Civic are commonly affected by P0173 due to their specific fuel management systems.
How can I prevent P0173 from happening again?
Regular maintenance such as checking the MAF sensor, inspecting vacuum lines, and ensuring proper fuel system function can help prevent P0173 from recurring.
What is P0173?
The P0173 code indicates that there is a fuel trim malfunction detected in bank 2 of the engine. This code is primarily associated with the air-fuel mixture being too rich or too lean, which can lead to poor engine performance and increased emissions. When the engine control module (ECM) recognizes that the fuel trim values are outside the expected range, it triggers the P0173 code. This could be due to a faulty mass airflow sensor (MAF), vacuum leaks, or issues with the fuel delivery system. For example, many vehicles from Ford, such as the 2004-2008 F-150, and Honda models like the 2006-2011 Civic, are susceptible to this code due to their complex fuel management systems. If left unaddressed, a P0173 could lead to reduced fuel efficiency, rough idling, and potential engine damage over time. Therefore, it's crucial to understand the implications of this code and seek timely repairs to maintain optimal vehicle performance.
System: P - Powertrain (Engine, Transmission, Emissions)
Symptoms
Common symptoms when P0173 is present:
- Check engine light stays on constantly, indicating a persistent issue that needs attention.
- Engine hesitates during acceleration, which may manifest as a lack of power when trying to speed up.
- Fuel economy decreased by 10-15%, noticeable in your monthly fuel expenses.
- Rough idling or stalling, especially when the engine is cold or during low-speed maneuvers.
- Excessive exhaust emissions, which may be detected during vehicle inspections or by a noticeable smell.
Possible Causes
Most common causes of P0173 (ordered by frequency):
- The most common cause is a faulty mass airflow sensor (MAF), occurring in about 40% of cases. This sensor can give incorrect readings, leading to improper fuel trim adjustments.
- A second common cause is vacuum leaks, which can cause the engine to draw in excess air, upsetting the air-fuel ratio. Checking for cracked hoses or loose fittings is essential.
- Another cause could be an issue with the fuel delivery system, such as a clogged fuel filter or failing fuel pump. Regular maintenance can help prevent these issues.
- Less common but serious causes include a malfunctioning ECM, which may require reprogramming or replacement.
- In rare cases, a faulty oxygen sensor could also lead to incorrect readings and trigger a P0173 code.
P0173 Repair Costs
Cost Breakdown by Repair Type
Mass Airflow Sensor Replacement
Replacing a faulty MAF sensor can restore proper air-fuel mixture readings.
- Total: $150 - $300
- Success rate: 85%
Vacuum Leak Repair
Repairing or replacing damaged hoses or fittings can eliminate unwanted air intake.
- Total: $100 - $200
- Success rate: 75%
Fuel Pump Replacement
If the fuel pump is failing, replacing it will ensure proper fuel delivery.
- Total: $300 - $600
- Success rate: 90%
Money-Saving Tips for P0173
- 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 P0173 Diagnosis Process
Follow these systematic steps to accurately diagnose P0173. 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 (5-10 minutes)
Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion (5-10 minutes).
Step 2: Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context (10-15 minutes)
Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context (10-15 minutes).
Step 3: Step 3: Component testing - Use a multimeter or specific diagnostic tools to test suspected components, focusing on the MAF and oxygen sensors (20-30 minutes)
Step 3: Component testing - Use a multimeter or specific diagnostic tools to test suspected components, focusing on the MAF and oxygen sensors (20-30 minutes).
Step 4: Step 4: System function test - Verify proper operation after repairs and clear codes to monitor for any reoccurrence (10-15 minutes)
Step 4: System function test - Verify proper operation after repairs and clear codes to monitor for any reoccurrence (10-15 minutes).
Step 5: Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success and ensure the check engine light does not return (15-20 minutes)
Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success and ensure the check engine light does not return (15-20 minutes).
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: Mass Airflow Sensor Replacement on a 2006 Honda Civic
Vehicle: 2006 Honda Civic, 80,000 miles
Problem: The customer reported a check engine light and poor acceleration.
Diagnosis: Using the GeekOBD APP, we identified a P0173 code and confirmed a faulty MAF sensor.
Solution: Replaced the mass airflow sensor and cleared the code.
Cost: $250 (parts: MAF sensor: $180, labor: $70)
Result: The vehicle ran smoothly post-repair, and the check engine light remained off.
Case Study 2: Vacuum Leak Repair on a 2007 Ford F-150
Vehicle: 2007 Ford F-150, 95,000 miles
Problem: Customer complained of rough idling and poor fuel economy.
Diagnosis: Diagnosed with P0173 and confirmed a significant vacuum leak.
Solution: Replaced several cracked vacuum hoses.
Cost: $150 (parts: $50, labor: $100)
Result: The vehicle's performance improved significantly, and the check engine light was resolved.