← Back to Search Severity: Medium

P0398

P0398: Ignition System Misfire

Fix Cost
$100 - $500
Parts & Labor
Difficulty
3/5
Moderate
1-2 hours
DIY Possible?
✅ Yes
Save money
Category
Powertrain
System

📖 What Does P0398 Mean?

A misfire detected in one or more cylinders, affecting combustion efficiency, which can cause decreased engine performance, rough idling, and decreased fuel efficiency.
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Symptoms

  • Rough idling
  • decreased engine performance
  • decreased fuel efficiency
  • engine misfire
  • decreased power
  • and decreased acceleration.
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Common Causes

  • Faulty spark plug
  • faulty spark plug wire
  • faulty ignition coil
  • faulty fuel injector
  • faulty oxygen sensor
  • or a vacuum leak.
Fix Guide
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Possible Solutions

1. Check and replace the spark plug, spark plug wire, and ignition coil if faulty. 2. Check and clean the fuel injector and oxygen sensor. 3. Check for vacuum leaks and repair if necessary.

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Common Questions About P0398

Q

Can I drive with code P0398?

A

You can drive for a short time, but should address code P0398 soon to avoid worsening the problem or failing an emissions test.

Q

How much does it cost to fix P0398?

A

The estimated repair cost for code P0398 is between $100 and $500. This includes parts and labor for most makes and models.

Q

Is this code easy to fix myself?

A

This repair is considered moderate. It may require specialized tools or significant disassembly. Professional help is recommended if you aren't an experienced DIYer.

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Complex codes like P0398 can be tricky. Don't risk it if you're unsure.

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Related Diagnostic Codes

Other codes that may appear with P0398

💡 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