OBD Guide

P1398

Misfire Adaptive Numerator At Limit Condition

Severity
🔴 High
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–89 (est.)

Symptoms

  • Unstable engine idling
  • Power Loss
  • Increased fuel consumption
  • Jerking during acceleration
  • Check Engine Light Illuminates

Causes

  • Faulty spark plugs
  • Problems with ignition coils
  • Low fuel pressure
  • Dirty or faulty fuel injectors
  • Problems with the intake system (air leaks)

How to Fix

  1. Check the condition of the spark plugs and replace if necessary.
  2. Diagnose ignition coils
  3. Check fuel pressure and condition of the fuel pump
  4. Clean or replace fuel injectors
  5. Check the tightness of the intake system

Related codes

Error P1398 by Vehicle Brand