Understanding P0175 on the 2022 Buick Encore GX
The 2022 Buick Encore GX comes with either the 1.2L L3T turbocharged three-cylinder (137 hp) or the 1.3L L3T turbo three-cylinder (155 hp). When P0175 appears, the ECM has detected persistent over-fueling in the secondary fuel control loop. On these small-displacement turbo engines, precise fuel management is critical for both performance and efficiency, making P0175 a code you shouldn't ignore.
Symptoms to Watch For
- Check engine light on the Encore GX dashboard
- Fuel economy below the rated 29/32 MPG (1.3L) — particularly noticeable
- Dark exhaust smoke during acceleration or turbo spool
- Rough idle or engine vibration
- Fuel odor from the tailpipe
- Reduced power — significant on a small-displacement turbo engine
Common Causes on the Encore GX Turbo
1. MAF Sensor Contamination
The small turbo engines in the Encore GX are highly sensitive to MAF sensor accuracy. These three-cylinder engines use aggressive turbo boost to compensate for their small displacement, and even minor MAF contamination causes disproportionate fuel delivery errors. Dust, oil from aftermarket filters, or PCV blow-by are common causes. Cleaning costs $10–$15; GM OEM MAF is $90–$190.
2. Turbo Boost Control Problem
The Encore GX's turbo operates at relatively high boost ratios for its displacement. If the wastegate or boost control solenoid doesn't regulate properly, over-boost triggers the ECM's protective fuel enrichment. A stuck wastegate is more problematic on these small engines because the percentage of over-boost is larger relative to total airflow. Repair costs $150–$380.
3. O2 Sensor Malfunction
The wideband oxygen sensor provides fuel mixture feedback to the ECM. A contaminated or failing sensor causes incorrect readings that prompt the ECM to add fuel. On the Encore GX, the sensor is accessible from underneath the vehicle. Replacement costs $100–$240 at a Buick dealer.
4. Fuel Injector Issue
The 1.2L and 1.3L turbo engines use direct injection at high pressures. An injector with incorrect flow rate or carbon deposits on the tip can cause over-fueling. On these small engines, a single misbehaving injector has a proportionally larger effect. Cleaning costs $100–$200; injector replacement is $80–$160 per unit plus labor.
Diagnostic Steps
- Scan for all codes — look for boost-related companion codes
- Check fuel trim data — LTFT below -10% confirms persistent rich correction
- Clean the MAF sensor as the easiest first step
- Compare actual vs. commanded boost with a scan tool
- Monitor O2 sensor voltage and response time
- Check air filter and intake tract for obstructions or leaks
Driving Considerations
The Encore GX is a subcompact crossover designed for efficient city driving. With P0175, you lose the efficiency advantage that makes these small turbo engines appealing. Drive normally but avoid heavy throttle. The Encore GX's catalytic converter costs $500–$1,000, which while less than luxury brands, is still worth protecting. Address the code within two weeks.
Repair Affordability
The Encore GX is one of Buick's most affordable models, and repair costs reflect that. Buick dealer labor runs $120–$160/hour. GM parts for the 1.2L and 1.3L engines are reasonably priced compared to larger GM powertrains. An independent GM-experienced shop can save 20–30%. The 2022 model may still be within the 5-year/60,000-mile powertrain warranty — check before paying.