P0131 on the 2024 Dodge Hornet
Your 2024 Dodge Hornet has set code P0131, indicating the Bank 1 Sensor 1 oxygen sensor is reading persistently below the ECM's expected voltage range. The 2024 Hornet continues with the 2.0L turbocharged four-cylinder (GME-T4) producing 268 hp on the GT trim, or the 1.3L turbo with PHEV system on the R/T. Since both engines are inline configurations, there's only one bank — Bank 1 Sensor 1 is the upstream sensor between the turbo outlet and the catalytic converter.
What You May Notice
- Check engine light on the dashboard
- Slightly worse fuel economy
- Rough idle or minor vibration at low RPM
- Subtle hesitation during acceleration
- Vehicle may feel slightly down on power
Causes on the 2024 Hornet
1. Defective O2 Sensor
On a 2024 model, a factory-defective sensor is the most likely cause. The turbo engine's high exhaust gas temperatures put extreme stress on the sensor, and quality control variations in sensor manufacturing can produce units that fail early. The sensing element may have an internal defect that causes it to read consistently low voltage.
2. Assembly-Related Wiring Issue
The Hornet's compact engine bay, shared with the Alfa Romeo Tonale, packs the turbo, exhaust, and sensor wiring into tight quarters. A wire pinched during assembly, a connector not fully seated, or improper harness routing near the turbo can cause signal issues. These are manufacturing defects rather than wear items on a vehicle this new.
3. Exhaust Gasket Leak
The turbo-to-downpipe connection uses a gasket and bolted flange. If this wasn't properly torqued at the factory, or if the gasket is defective, it can leak and introduce fresh air past the O2 sensor. The small leak is enough to trigger P0131 without any other noticeable symptoms.
4. ECM Software Issue
New vehicles on new platforms sometimes have ECM calibration issues. The P0131 threshold may be set too aggressively for the sensor's normal operating range, or the sensor warm-up monitoring strategy may flag false positives. Check with your dealer for applicable TSBs or software updates.
What to Do
- Schedule a dealer appointment immediately — this is a warranty repair.
- If you want to verify yourself first, scan live data for Bank 1 Sensor 1 voltage (should cycle 0.1V–0.9V at warm idle).
- Check the sensor connector for proper seating — sometimes it's as simple as re-clicking the connector.
- Ask the dealer to check for TSBs related to P0131 on the Hornet platform.
- Do not attempt DIY repairs that could void your warranty.
Repair Costs
This should be fully covered under the 2024 Hornet's 3-year/36,000-mile bumper-to-bumper warranty and the 8-year/80,000-mile federal emissions warranty. Out of pocket (if somehow needed), expect $160–$320 for sensor replacement or $100–$400 for exhaust work.
Bottom Line
Take your 2024 Hornet to the dealer. It's a free repair under warranty, and attempting DIY fixes on a vehicle this new could complicate your warranty coverage. The repair is typically quick — most dealers can have you in and out within a few hours.