---
id: faq-0068
title: "How long do Subaru spark plugs last, and when should they be replaced?"
category: faq
subtopic: service-and-maintenance
page_type: faq
source_url: "https://www.castlesubarumchenry.com"
tags: ["spark-plugs", "engine-maintenance", "tune-up"]
questions:
  - "When do I need new spark plugs?"
  - "How often should spark plugs be replaced?"
  - "What's the spark plug lifespan?"
related: [maintenance-schedule, genuine-parts, service-cost]
dealer: Castle Subaru McHenry
---

Modern Subaru spark plugs are built to last longer than older versions. Many new Subarus use long-life spark plugs good for 60,000-100,000 miles, though some older models may need replacement every 30,000-40,000 miles. Your owner's manual specifies the interval for your year and model.

Worn spark plugs can reduce fuel economy, cause rough idle, or trigger a check-engine light. If you notice hesitation on acceleration or poor gas mileage, a spark plug inspection might be in order.

Castle Subaru McHenry's Service experts can check your spark plugs and recommend replacement with genuine Subaru plugs if needed. Call (779) 601-0797 to find out when your Subaru's spark plugs are due.