P0171 on Your 2024 Acura TLX
A P0171 code on your 2024 Acura TLX means the ECM has detected a lean air-fuel mixture on Bank 1. The 2024 TLX uses a 2.0L turbocharged four-cylinder producing 272 horsepower, while the Type S has a 3.0L twin-turbo V6 with 355 horsepower. A lean condition means the air-fuel ratio has too much air or too little fuel.
As a 2024 model, your TLX is under Acura's factory warranty. Here is what to understand about this code.
Symptoms
- Check engine light on
- Rough idle
- Turbo hesitation during acceleration
- Reduced fuel economy
- Possible boost reduction
- Less responsive throttle
Common Causes
- Boost Leak (35% likelihood) - Factory assembly issues with turbo plumbing connections can cause pressurized air to bypass the MAF sensor.
- MAF Sensor Defect (25% likelihood) - A factory-defective or contaminated MAF sensor can cause lean fueling.
- Fuel System Defect (20% likelihood) - A defective injector or high-pressure pump issue.
- ECM Calibration (20% likelihood) - A software update may address fuel trim behavior.
Diagnostic Steps
- Dealer TSB check. Check for service bulletins.
- Fuel trim monitoring. LTFT above +10% confirms lean.
- Turbo plumbing inspection. Check all connections and clamps.
- MAF evaluation. Compare to factory specs.
- Software check. An ECM reflash may be available.
Repair Costs
- Under warranty: $0. Fully covered.
- Boost pipe repair (out of warranty): $75 - $350.
- MAF sensor (out of warranty): $200 - $350.
- Fuel system (out of warranty): $300 - $1,000.
- ECM reflash (out of warranty): $100 - $200.
Acura Warranty
The 2024 TLX has a 4-year/50,000-mile basic warranty and 6-year/70,000-mile powertrain warranty. P0171 is covered. Visit your Acura dealer for no-cost service.
Prevention Tips
- Use OEM air filters
- Fill up with premium fuel
- Avoid aftermarket intake modifications on a new vehicle
- Respond to check engine lights promptly
- Follow the factory maintenance schedule