P0174 on Your 2024 Acura Integra
The 2024 Acura Integra features the 1.5L turbocharged four-cylinder (L15CA) making 200 horsepower in standard trim, or the Type S with a 2.0L turbo (K20C4) producing 320 horsepower. P0174 indicates a lean condition — the PCM has detected too much air or too little fuel in the combustion mixture. Since both engines are inline-fours, this code represents a generalized lean state rather than a bank-specific issue.
Symptoms to Watch For
- Check engine light on
- Slight idle roughness or surging
- Hesitation or stumble during acceleration
- Reduced turbo boost feel
- Fuel economy drop below normal range
Causes of P0174 on the 2024 Integra
1. Boost Leaks
Both Integra engines are turbocharged. The charge air system includes the turbo compressor outlet, intercooler, and piping to the throttle body. On a 2024 model, a factory assembly issue such as an undertorqued hose clamp or improperly seated coupler could cause a leak. The Type S K20C4 has a higher boost threshold, making even small leaks more impactful. Test with regulated shop air at 15-20 psi.
2. MAF Sensor Contamination
The Integra's enthusiast-oriented market means aftermarket air intakes and oiled filters are common modifications. These can contaminate the MAF sensor quickly, causing underreading of airflow and lean fuel delivery. Even on a stock vehicle, PCV oil vapor can coat the sensor over time. Clean with MAF-specific cleaner only.
3. Fuel Delivery Shortfall
Both engines use direct fuel injection with high-pressure pumps. The Type S K20C4 has higher fuel flow demands than the 1.5L. A high-pressure pump losing output, a restricted fuel filter, or dirty injectors can starve the engine. Poor fuel quality or water-contaminated fuel can also contribute.
4. Intake Manifold Gasket Leak
An improperly seated intake manifold gasket can allow unmetered air past the MAF sensor. On a new vehicle, this would typically be a factory defect. The leak creates a consistent lean condition at all RPMs, unlike a boost leak which worsens with engine load.
Diagnostic Procedure
- Scan for DTCs and review freeze frame data for fuel trim values
- Check if aftermarket intake modifications were installed
- Perform a boost leak test on the charge air system
- Inspect all charge pipe connections, couplers, and clamps
- Clean and test the MAF sensor
- Monitor fuel rail pressure via a scan tool
Repair Costs
Under warranty, repairs should be free. Reference costs for out-of-warranty:
- Boost leak repair: $100–$350
- MAF sensor cleaning: $15–$35 (DIY)
- MAF sensor replacement: $150–$320
- High-pressure fuel pump: $400–$800
- Intake manifold gasket: $200–$400
Driving Considerations
Running lean on a turbo engine creates knock risk, especially under boost. The Integra's knock sensors provide some protection by pulling ignition timing, but this reduces power and cannot fully prevent damage in severe cases. Avoid spirited driving until diagnosed. Light commuting is acceptable for a few days.
Warranty Coverage
The 2024 Integra is covered by Acura's 4-year/50,000-mile basic warranty and 6-year/70,000-mile powertrain warranty. Any manufacturing defect causing P0174 should be repaired at no cost. Note: aftermarket intake modifications may affect warranty coverage for related components, so discuss with your dealer.