P0173 Code - Fuel Trim Malfunction Bank 2
Quick Answer
With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the theoretical mixture ratio based on the mixture ratio feedback signal from the heated oxygen sensors 1. Common causes include Intake air leaks, Faulty front heated oxygen sensor, Ignition misfiring. 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
- P0173 indicates Fuel Trim Malfunction Bank 2.
- Common causes
- Common causes include Intake air leaks, Faulty front heated oxygen sensor, Ignition misfiring.
- 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.
Code P0173 Description
In case the amount of the compensation value is extremely large (The actual mixture ratio is too lean.), the ECM judges the condition as the fuel injection system malfunction and light up the MIL (2 trip detection logic).
What are the Possible Causes of the DTC P0173?
- Intake air leaks
- Faulty front heated oxygen sensor
- Ignition misfiring
- Faulty fuel injectors
- Exhaust gas leaks
- Incorrect fuel pressure
- Lack of fuel
- Faulty Mass Air Flow (MAF) sensor
- Incorrect Positive Crankcase Ventilation (PCV) hose connection
How to Fix the DTC P0173?
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.
Code Tech Notes
User Submitted Video
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0173 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.
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Information for Specific Makes
- P0173 BMW — Fuel Trim Malfunction Bank 2
- P0173 Chrysler — Fuel System 2/1 Rich Control Over Limit
- P0173 Dodge — Fuel System 2/1 Rich Control Over Limit
- P0173 Ford — Fuel Trim Malfunction Bank 2
- P0173 Hyundai — Fuel Trim Bank 2
- P0173 Jeep — Fuel System 2/1 Rich Control Over Limit
- P0173 KIA — Fuel Trim Bank 2
- P0173 Lincoln — Fuel Trim Malfunction Bank 2
- P0173 Mazda — Bank 2 Adaptive Fuel Table At Calibrated Limit
- P0173 Mercedes-Benz — Fuel Trim Malfunction Bank 2
- P0173 Mercury — Fuel Trim Malfunction Bank 2
- P0173 Mitsubishi — Fuel Trim Malfunction Bank 2
Frequently Asked Questions about P0173 Code
1. What are common symptoms of OBDII code P0173 (Fuel Trim Malfunction Bank 2)?
- Common symptoms include rough idling, decreased fuel efficiency, engine misfires, and a noticeable decrease in engine performance.
2. What are the possible causes of OBDII code P0173 (Fuel Trim Malfunction Bank 2)?
- Potential causes include a vacuum leak, faulty oxygen sensor, clogged fuel injectors, fuel pressure regulator issues, or a malfunctioning mass airflow sensor.
3. How can I diagnose the OBDII code P0173 (Fuel Trim Malfunction Bank 2)?
- Diagnosis typically involves using an OBDII scanner to retrieve the code, inspecting the affected bank's oxygen sensor, checking for vacuum leaks, and testing the fuel injectors and other related components.
4. Can a dirty or clogged air filter trigger OBDII code P0173 (Fuel Trim Malfunction Bank 2)?
- Yes, a dirty or clogged air filter can disrupt the air-fuel mixture ratio, potentially leading to a lean condition in Bank 2 and triggering the P0173 code.
5. What should I do if I get OBDII code P0173 (Fuel Trim Malfunction Bank 2)?
- It is recommended to address the underlying issue promptly to prevent further damage to the engine. Consult a mechanic to accurately diagnose and repair the problem.
6. How can I prevent OBDII code P0173 (Fuel Trim Malfunction Bank 2) from occurring?
- Regular maintenance, such as changing the air filter and ensuring all engine components are in good working condition, can help prevent issues that may trigger the P0173 code.
7. Can driving with OBDII code P0173 (Fuel Trim Malfunction Bank 2) cause long-term damage to the vehicle?
- Continuing to drive with this code may lead to reduced engine performance, decreased fuel efficiency, and potential damage to the catalytic converter over time.
8. Is it safe to clear OBDII code P0173 (Fuel Trim Malfunction Bank 2) using an OBDII scanner?
- Clearing the code without addressing the underlying issue may temporarily turn off the check engine light, but the problem will persist and likely trigger the code again in the future.
9. How much does it typically cost to repair OBDII code P0173 (Fuel Trim Malfunction Bank 2)?
- The cost of repair varies depending on the cause of the issue, but it can range from a simple fix like replacing a faulty sensor to a more complex repair involving multiple components.
10. Can a DIY enthusiast fix OBDII code P0173 (Fuel Trim Malfunction Bank 2) at home?
- While some causes of the P0173 code may be addressed by DIY enthusiasts, it's recommended to consult a professional mechanic for an accurate diagnosis and proper repair to ensure the issue is fully resolved.
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