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P0174 Code: System Too Lean Bank 2
P0174 means bank 2 is getting too much air or not enough fuel. Learn the common symptoms, causes, severity, and typical repair costs.
The P0174 code means bank 2 is getting too much air or not enough fuel. It is stored when the engine computer sees a signal or operating condition outside the expected range.
Air and fuel metering codes point to fuel mixture, intake sensor, oxygen sensor, or temperature data problems. The right fix depends on live data, freeze-frame information, service history, and whether other codes are present.
Symptoms
- Check engine light
- Rough idle
- Hesitation
- Poor fuel economy
- Engine surging
- Possible misfire symptoms
Common Causes
- Vacuum leak affecting bank 2
- Dirty mass airflow sensor
- Weak fuel pump
- Clogged injector
- Exhaust leak before the oxygen sensor
- Faulty oxygen sensor
Severity
Moderate to high. Lean conditions can create misfires, heat, and converter damage when severe.
Typical Repair Costs
$50 to $1,200
- The lower end usually covers inspection, cleaning, wiring repair, or a simple sensor replacement.
- The higher end applies when parts are hard to access or when the code is caused by a larger mechanical, emissions, or transmission problem.
- Always diagnose before replacing parts, because one code can be triggered by several related systems.
Frequently Asked Questions
What does code P0174 mean?
P0174 means bank 2 is getting too much air or not enough fuel. The exact cause should be confirmed with diagnostic data before replacing parts.
Can I drive with a P0174 code?
It depends on symptoms. If the car runs poorly, overheats, stalls, shifts harshly, or the check engine light flashes, limit driving and diagnose it promptly.
What is the most common fix for P0174?
Common fixes include addressing vacuum leak affecting bank 2, dirty mass airflow sensor, weak fuel pump, but testing is needed to avoid replacing the wrong part.
Related Articles
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P0171 means the engine is running too lean on bank 1, often from extra air, not enough fuel, or incorrect sensor data.
Oxygen Sensor Failure Symptoms, Causes, and Repair Cost
A failing oxygen sensor can affect fuel mixture, emissions, fuel economy, and catalyst efficiency codes.
Rough Idle: Symptoms, Causes, and Repair Cost
A rough idle can come from air, fuel, ignition, sensor, or mechanical issues.
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