What P0175 Means on the 2024 Honda Accord
The P0175 code on your 2024 Honda Accord indicates the ECM has detected a rich condition on bank 2 — too much fuel in the combustion mixture. The 2024 Accord (11th generation) is available with the 1.5L turbocharged four-cylinder engine (192 hp, 192 lb-ft) or the 2.0L Atkinson-cycle hybrid powertrain. Since P0175 is a fuel-system code, it applies to the 1.5T conventional powertrain. This direct-injected turbo engine uses precise electronic fuel management, and a P0175 on a nearly new vehicle typically points to a component defect.
Symptoms to Expect
- Check engine light on the dashboard
- Noticeable fuel smell from the exhaust
- Slightly rough or uneven idle
- Black smoke or soot residue at the tailpipe
- Fuel economy drops below the rated 29–33 mpg
- Engine may feel slightly down on power
Root Causes on the 2024 Accord
1. Defective Oxygen Sensor (High Likelihood)
A factory-defective O2 sensor is the most probable cause on a 2024 Accord. If the sensor reads falsely lean, the ECM compensates by adding fuel, creating an actual rich condition. The 2024 Accord uses wideband air-fuel ratio sensors upstream and conventional O2 sensors downstream. A faulty sensor on bank 2 will specifically trigger P0175. The dealer can compare sensor readings between banks and verify switching response.
2. Fuel Injector Leak (Medium Likelihood)
The 1.5T's direct injectors operate at pressures exceeding 200 bar. A manufacturing defect in an injector's sealing or needle valve can allow fuel to drip when the injector should be closed. Even a small leak adds significant extra fuel over time. This is more common on direct injection systems than port injection due to the extreme operating conditions.
3. Fuel Pressure Regulator or Sensor Fault (Medium Likelihood)
The electronic fuel pressure control on the 2024 Accord's 1.5T manages rail pressure via the high-pressure fuel pump. A faulty fuel pressure sensor that reads low will cause the ECM to command higher pump output, resulting in elevated fuel pressure and excess fuel delivery. Similarly, a software calibration error can affect fuel pressure targeting.
4. EVAP System Purge Valve Stuck Open (Low Likelihood)
A purge valve that's stuck in the open position continuously feeds fuel vapor from the charcoal canister into the intake manifold. This adds unmetered fuel on top of the ECM's calculated injection, creating a rich condition. The purge valve on the 2024 Accord is electronically controlled and a defect would be a manufacturing issue.
Diagnostic Steps
- Check TSBs and software updates — Honda may have published guidance for P0175 on 2024 Accord models.
- Monitor fuel trims — Negative LTFT below -10% on bank 2 confirms the rich condition.
- Test O2/A-F sensors — Compare bank 1 and bank 2 sensor readings for inconsistencies.
- Check fuel pressure — Monitor rail pressure under various conditions using the dealer's diagnostic system.
- Test EVAP purge valve — Command the valve open and closed to verify proper operation.
Cost Estimates (If Out of Warranty)
- O2/A-F sensor replacement: $130–$300
- Fuel injector replacement: $180–$450 per injector
- Fuel pressure regulator/sensor: $200–$400
- EVAP purge valve: $90–$200
Warranty Coverage
Your 2024 Accord is covered by Honda's 3-year/36,000-mile basic warranty and 5-year/60,000-mile powertrain warranty. P0175 involves fuel system and emissions components covered under these warranties. The federal emissions warranty covers O2 sensors and catalytic converters for 8 years/80,000 miles. Take your Accord to a Honda dealer for a no-cost repair.
Should You Keep Driving?
A rich condition is less immediately harmful than lean, but it still causes issues. Excess fuel can contaminate engine oil, foul spark plugs, and damage the catalytic converter. The 1.5T Accord engine has seen improved fuel dilution countermeasures in the 11th generation, but running rich can still contribute to oil contamination. Since your 2024 Accord is under warranty, schedule a dealer visit within a week.