What causes P1171 on a Honda?

Plugged fuel filter or low fuel pressure Faulty or dirty mass airflow sensor Weak fuel pump Vacuum leak in the intake

How do I fix P1171 on a Honda?

Confirm the code with a scan tool and check for related faults Inspect the sensor and its connector for corrosion, moisture, and loose pins Check the wiring for an open or short between the sensor and the control module Test the sensor signal against the factory spec before replacing parts Replace the sensor if it fails testing, then clear codes and retest

P1171 The powertrain control module saw the fuel system run lean during acceleration

Q: What does P1171 mean on a Honda?

P1171. The powertrain control module saw the fuel system run lean during acceleration. The engine may hesitate or lose power when you press the throttle.. Applies to Honda and Acura models that use this code.

Category: Powertrain - Fuel/Air Metering
Severity: Check Engine Light
Applies to: Honda and Acura models that use this code

What does P1171 mean on a Honda?

P1171. The powertrain control module saw the fuel system run lean during acceleration. The engine may hesitate or lose power when you press the throttle.. This Honda-enhanced code applies to Honda and Acura models that use this code.

Common causes of P1171

Plugged fuel filter or low fuel pressure
Faulty or dirty mass airflow sensor
Weak fuel pump
Vacuum leak in the intake

How to fix P1171

Confirm the code with a scan tool and check for related faults
Inspect the sensor and its connector for corrosion, moisture, and loose pins
Check the wiring for an open or short between the sensor and the control module
Test the sensor signal against the factory spec before replacing parts
Replace the sensor if it fails testing, then clear codes and retest

Sources and review

Checked against two independent sources.
Last updated 2026-10-02.