← View Generic P0172 Guide Severity: Medium
🚗 Vehicle-Specific Guide

This guide is customized for your 2021 Honda PASSPORT

P0172: System Too Rich Bank 1

on 2021 Honda PASSPORT

Fix Cost
$30 - $300
Parts & Labor
Difficulty
3/5
1-3 hours
DIY Possible?
✅ Yes
Save money
Your Vehicle
2021 Honda
PASSPORT
⚠️

Important for 2021 Honda PASSPORT Owners

Before starting repairs, verify which engine your 2021 Honda PASSPORT has. Check your VIN or engine code to ensure you order the correct parts.

📖 What Does P0172 Mean on 2021 Honda PASSPORT?

The engine is running with too much fuel and not enough air on bank 1. The oxygen sensor is detecting a rich fuel mixture that the engine control module cannot adequately correct.
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Symptoms

  • • Black smoke from exhaust
  • • strong fuel odor
  • • poor fuel economy
  • • rough idle
  • • fouled spark plugs
  • • check engine light
  • • carbon buildup.
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Common Causes

  • • Faulty oxygen sensors
  • • leaking fuel injectors
  • • high fuel pressure
  • • dirty air filter
  • • faulty mass airflow sensor
  • • carbon canister purge valve stuck open.
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How to Fix P0172 on 2021 Honda PASSPORT

Replace faulty oxygen sensors, clean or replace fuel injectors, check fuel pressure regulator, replace air filter, clean mass airflow sensor, test purge valve operation.

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Need Maintenance Info for Your PASSPORT?

Get oil capacity, filter specs, and torque settings for your specific 2021 Honda PASSPORT.

View 2021 Honda PASSPORT Specs

Parts for 2021 Honda PASSPORT

MAF Sensor Shop ↗ Fuel Filter Shop ↗ Vacuum Hoses Shop ↗ Fuel Injector Cleaner Shop ↗

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OBD2 Scanner

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Related Diagnostic Codes

Other codes that may appear with P0172

P0175 Same System

System Too Rich Bank 2

Medium
P0420 Related Problem

Catalyst System Efficiency Below Threshold Bank 1

Medium
P0430 Related Problem

Catalyst System Efficiency Below Threshold Bank 2

Medium

💡 Why These Codes Are Related:

  • • Similar Issues: Same root cause or component failure
  • • Related Problems: Often occur together due to system interactions
  • • Sequential Codes: Progressive failure stages or multiple sensors
  • • Same System: Components within the same automotive system