OBD Guide

P0172

System Too Rich Bank 1

P0172 is an OBD-II diagnostic trouble code meaning: System Too Rich Bank 1. Common causes: dmrv malfunction, fuel leak in injectors. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Increased fuel consumption
  • Black smoke from the exhaust pipe
  • Reduced engine power
  • Unstable idling

Causes

  • DMRV malfunction
  • Fuel leak in injectors
  • Dirty or faulty spark plugs
  • Oxygen sensor malfunction
  • Problems with the EVAP system
  • Air filter clogged

How to Fix

  1. Check the air flow sensor for contamination or malfunction
  2. Diagnose injectors for leaks
  3. Check spark plugs
  4. Check oxygen sensor
  5. Inspect the EVAP system for leaks
  6. Replace the air filter if necessary

Related codes

Error P0172 by Vehicle Brand

FAQ

What does the P0172 code mean?

P0172 is an OBD-II diagnostic trouble code that indicates: System Too Rich Bank 1

What causes a P0172 error code?

The most common causes of P0172 include: DMRV malfunction; Fuel leak in injectors; Dirty or faulty spark plugs; Oxygen sensor malfunction.

How do I fix a P0172 diagnostic trouble code?

To fix P0172: Check the air flow sensor for contamination or malfunction. Diagnose injectors for leaks. Check spark plugs. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P0172?

Limited driving only, diagnose soon

How much does it cost to fix P0172?

The estimated repair cost for P0172 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat