P0171 Code: 2024 Buick Enclave – What It Means & Cost to Fix

2024 Buick Enclave P0171 System Too Lean Fix

What Does P0171 Mean on Your 2024 Buick Enclave?

Your 2024 Buick Enclave has triggered a P0171 code, meaning the engine control module has detected a lean air-fuel mixture on Bank 1. The completely redesigned 2024 Enclave features a new 2.5-liter turbocharged four-cylinder engine producing 328 horsepower, replacing the previous 3.6L V6. Since this is a four-cylinder engine, Bank 1 refers to the single cylinder bank. The ECM is compensating by adding extra fuel to balance the mixture.

Symptoms You Might Notice

  • Illuminated check engine light
  • Rough or unsteady idle
  • Hesitation or lag when pressing the accelerator
  • Fuel economy lower than the expected 23-29 MPG
  • Subtle vibration at idle or low speeds
  • Reduced power feel compared to normal operation

Common Causes of P0171 on the 2024 Buick Enclave

As a brand-new model with a new engine, warranty coverage is your best friend here:

  1. Boost or Intake Leak (30% likelihood) — The new turbo engine has charge pipes and intercooler connections that may not be perfectly sealed from the factory.
  2. ECU Calibration Issue (30% likelihood) — First-year production of the new 2.5T engine may have fuel mapping refinements available via software update.
  3. MAF Sensor Problem (25% likelihood) — A contaminated or miscalibrated mass air flow sensor causing incorrect airflow readings.
  4. Fuel Delivery Component (15% likelihood) — A weak fuel pump, fuel pressure sensor issue, or injector problem preventing proper fuel supply.

How to Diagnose the Problem

  1. Visit your Buick dealer — The 2024 Enclave is covered by GM's 3-year/36,000-mile bumper-to-bumper warranty plus 5-year/60,000-mile powertrain warranty. Let the dealer diagnose this at no cost.
  2. Ask about TSBs — New engine platforms often have Technical Service Bulletins addressing calibration and fuel trim issues.
  3. If diagnosing yourself — Use a quality OBD-II scanner to check fuel trim values and freeze frame data.
  4. Smoke test — A smoke machine pumped into the intake will reveal any hidden boost leaks.
  5. Monitor fuel pressure — The scan tool can show fuel rail pressure in real time to identify delivery issues.

Repair Options and Cost Breakdown

  • Boost or intake leak repair: $100–$350. Should be covered under warranty for a new vehicle.
  • ECU software update: $0–$200. Free under warranty or TSB. Standard dealer labor rate applies out of warranty.
  • MAF sensor replacement: $130–$280. Part cost is $50–$130. Easy DIY if out of warranty.
  • Fuel system repair: $400–$900. Covered under powertrain warranty. Out of pocket costs vary by specific component.

Prevention Tips

  • Use quality fuel from Top Tier stations
  • Keep up with all scheduled dealer maintenance
  • Report any performance changes to the dealer while under warranty
  • Use GM-recommended oil and filter specifications
  • Avoid aftermarket intake modifications without proper tuning

Warranty Coverage

Your 2024 Buick Enclave is covered by GM's comprehensive warranty: 3 years/36,000 miles bumper-to-bumper and 5 years/60,000 miles powertrain. Any P0171-related engine or fuel system repair should be covered at no cost. Always go to the dealer first before paying for outside repairs.

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