What P0174 Means on Your 2020 Honda Ridgeline
A P0174 code on the 2020 Honda Ridgeline signals a lean air-fuel mixture on Bank 2. The 2020 Ridgeline is powered by a 3.5-liter V6 engine producing 280 hp and 262 lb-ft of torque with i-VTEC, paired with a 9-speed automatic transmission and available all-wheel drive. With a V6 configuration, the engine has two cylinder banks. Bank 2 is the rear bank closest to the firewall, and that is where the lean condition has been detected.
Running lean means those cylinders are getting too much air relative to fuel. This causes higher combustion temperatures, rough operation, and can lead to costly engine damage if ignored.
Symptoms
- Check engine light on
- Rough or uneven idle
- Hesitation on acceleration
- Reduced power and torque
- Engine running hotter
- Misfires on Bank 2 cylinders
Common Causes on the 3.5L V6
- Vacuum Leak on Bank 2 - Aging hoses, intake runner gaskets, or PCV connections on the rear bank allow unmetered air to enter. The Ridgeline's engine bay makes rear bank access challenging.
- Dirty MAF Sensor - A contaminated sensor underreports total airflow. If only Bank 2 is lean, a bank-specific issue is more likely.
- Clogged Fuel Injector on Bank 2 - Carbon deposits restrict fuel flow through one or more rear bank injectors.
- Faulty Bank 2 O2 Sensor - A sluggish or inaccurate upstream O2 sensor on Bank 2 causes wrong fuel trim adjustments.
Diagnostic Steps
- Scan all codes - Check for P0171 alongside P0174.
- Vacuum leak inspection - Focus on rear bank. Smoke test recommended.
- Clean the MAF - Quick first step.
- Compare bank fuel trims - Isolate the issue to Bank 2.
- Injector balance test - Identify restricted injectors.
Repair Costs
The Ridgeline shares its powertrain with the Pilot, so costs are similar.
- Vacuum hose repair - $5 to $30, plus $80 to $160 labor.
- Intake manifold gasket - $40 to $90, plus $250 to $450 labor.
- MAF sensor cleaning - $10 to $25.
- MAF sensor replacement - $90 to $200, plus $50 to $100 labor.
- Fuel injector replacement - $60 to $140 per injector, plus $210 to $400 labor.
- O2 sensor replacement - $70 to $170, plus $80 to $160 labor.
DIY Feasibility
MAF sensor work is easy. Front-side vacuum checks are manageable. Rear bank work on the Ridgeline is tight but not impossible for experienced DIYers. O2 sensor replacement requires a sensor socket and patience. Intake gasket and injector work on the rear bank may warrant professional help.
Prevention Tips
- Inspect vacuum hoses during regular maintenance
- Use quality air filters
- Run fuel system cleaner periodically
- Follow Honda's maintenance schedule
- Address check engine lights promptly