What Does P0171 Mean on Your 2024 Buick Envision?
A P0171 code on your 2024 Buick Envision means the engine control module has detected a lean air-fuel condition. The 2024 Envision is powered by a 2.0-liter turbocharged four-cylinder engine (LSY) producing 228 horsepower. As an inline engine with one bank, P0171 means the entire engine is running lean — the ECM is adding extra fuel to compensate for excess air in the mixture.
Symptoms You Might Notice
- Illuminated check engine light
- Rough or shaky idle
- Sluggish throttle response
- Decreased fuel economy from the normal 26-31 MPG
- Subtle power loss during acceleration
- Occasional vibration at low RPMs
Common Causes of P0171 on the 2024 Buick Envision
- Boost or Intake Leak (30% likelihood) — Check charge pipe connections, intercooler hoses, and the intake manifold gasket. New vehicles can have improperly torqued clamps.
- ECM Software Update Needed (30% likelihood) — GM may have released fuel trim calibration updates for the 2.0T engine since production.
- MAF Sensor Problem (25% likelihood) — A defective or contaminated mass air flow sensor can cause the ECM to miscalculate fuel requirements.
- Fuel System Issue (15% likelihood) — A weak fuel pump, faulty pressure sensor, or sticking injector can prevent proper fuel delivery.
How to Diagnose the Problem
- Take it to the dealer — Your 2024 Envision is under warranty. Let Buick diagnose and repair it at no cost.
- Request TSB check — Ask specifically about Technical Service Bulletins for fuel trim issues on the 2.0T platform.
- Independent diagnosis — If preferred, use an OBD-II scanner to check fuel trims and freeze frame data.
- Smoke test — Professional leak detection for the turbo intake system.
- Live data monitoring — Watch MAF readings, fuel pressure, and O2 sensor response during a test drive.
Repair Options and Cost Breakdown
- Boost or intake leak repair: $100–$300. Warranty-covered on new vehicles.
- ECM software update: $0–$150. Free under warranty or applicable TSB.
- MAF sensor replacement: $120–$250. Part cost is $45–$100. Easy DIY if warranty has expired.
- Fuel system repair: $350–$750. Covered under powertrain warranty.
Prevention Tips
- Use quality fuel from Top Tier stations
- Keep up with scheduled dealer maintenance visits
- Use GM-recommended oil specifications
- Report performance changes to the dealer while under warranty
- Avoid aftermarket intake or exhaust modifications without proper tuning
Warranty Coverage
The 2024 Buick Envision comes with GM's 3-year/36,000-mile bumper-to-bumper warranty and 5-year/60,000-mile powertrain warranty. Any engine or fuel system component causing P0171 should be repaired free of charge at your authorized Buick dealer.