P0171 on Your 2024 Acura RDX
A P0171 code on your 2024 Acura RDX means the ECM detected a lean air-fuel mixture. The 2024 RDX continues with the 2.0L turbocharged four-cylinder engine (K20C6) producing 272 horsepower. Bank 1 covers the entire inline-four engine. A lean condition means too much air or insufficient fuel in the combustion process.
As a 2024 model under warranty, your best path is the Acura dealer. Here is what to know about the issue.
Symptoms
- Check engine light on
- Rough idle
- Turbo lag or hesitation
- Reduced fuel economy
- Possible reduced boost
- Less responsive throttle
Common Causes
- Boost Leak (35% likelihood) - Factory assembly issues with turbo hose clamps or charge pipe connections can cause pressurized air to bypass the MAF sensor.
- MAF Sensor Defect (25% likelihood) - A factory-defective or contaminated MAF sensor can misread airflow on the turbocharged engine.
- Fuel System Component (20% likelihood) - A defective fuel injector or high-pressure fuel pump issue.
- ECM Calibration (20% likelihood) - Honda/Acura may have a software update for the 2024 RDX addressing fuel trim behavior.
Diagnostic Steps
- Dealer TSB check. Have the dealer search for service bulletins.
- Fuel trim monitoring. LTFT above +10% confirms lean.
- Inspect turbo plumbing. Check all connections and clamps.
- MAF evaluation. Compare to factory specs.
- Software update check. An ECM reflash may be available.
Repair Costs
- Under warranty: $0. Fully covered.
- Boost pipe repair (out of warranty): $75 - $300.
- MAF sensor (out of warranty): $200 - $320.
- Fuel system (out of warranty): $300 - $950.
- ECM reflash (out of warranty): $100 - $200.
Acura Warranty
The 2024 RDX has a 4-year/50,000-mile basic warranty and 6-year/70,000-mile powertrain warranty. P0171 is a powertrain issue and should be repaired at no cost by an authorized Acura dealer.
Prevention Tips
- Use OEM air filters
- Fill up with premium fuel
- Avoid aftermarket intake modifications
- Respond to check engine lights promptly
- Follow the factory maintenance schedule