When should spark plugs be changed on a Lexus RX350?

Spark plugs are a critical component of the ignition system in a Lexus RX350, and they play a crucial role in the engine's performance. Knowing when to change the spark plugs can help maintain your vehicle's efficiency and prevent potential issues. In general, spark plugs in a Lexus RX350 should be replaced every 60,000 to 100,000 miles, depending on driving conditions and the manufacturer's recommendations.

Reasons to Change Spark Plugs

• Mileage Interval: Lexus recommends changing the spark plugs on the RX350 every 60,000 to 100,000 miles, or as specified in the owner's manual.


• Engine Performance Issues: Worn or faulty spark plugs can cause problems like rough idling, decreased fuel efficiency, and difficulty starting the engine.


• Increased Emissions: Degraded spark plugs can lead to increased emissions and reduced engine efficiency.


• Preventive Maintenance: Changing spark plugs as part of a regular maintenance schedule can help ensure your Lexus RX350 runs smoothly and efficiently.li>
  

By following the manufacturer's recommended spark plug replacement interval and addressing any performance issues, you can help maintain the optimal operation of your Lexus RX350 engine.

Signs It's Time to Change Spark Plugs

• Rough Idling: If your Lexus RX350 is experiencing rough or uneven idling, it may be a sign that the spark plugs need to be replaced.


• Decreased Fuel Efficiency: Worn spark plugs can cause your engine to run less efficiently, leading to a noticeable drop in fuel economy.li>
  
• Difficulty Starting: If your Lexus RX350 is having trouble starting, especially when the engine is cold, it could be an indication that the spark plugs need to be replaced.


• Engine Misfiring: Misfiring or hesitation during acceleration can be a sign of faulty spark plugs.

If you notice any of these symptoms in your Lexus RX350, it's a good idea to have the spark plugs inspected and replaced if necessary.

Spark Plug Replacement Process

Changing the spark plugs on a Lexus RX350 is generally a straightforward process that can be done by a qualified mechanic or a DIY-inclined owner. The process typically involves the following steps:

1. Locate the spark plug access points, usually under the engine's intake manifold or coil packs.


2. Disconnect the spark plug wires or coil packs to access the spark plugs.


3. Use a spark plug socket and a torque wrench to remove the old spark plugs.


4. Install the new spark plugs, ensuring they are the correct type and gap, and tighten them to the manufacturer's specified torque.


5. Reconnect the spark plug wires or coil packs.


6. Start the engine and check for any issues or leaks.

Following the proper spark plug replacement procedure and using the recommended parts can help ensure the continued reliable performance of your Lexus RX350.

Do I really need to change my spark plugs at 100,000 miles?

Yes, replacing spark plugs at 100,000 miles is a common and often necessary maintenance task, as many modern vehicles have spark plugs rated to last that long. However, the exact interval depends on your vehicle's make, model, and the type of spark plug installed, so you should always check your owner's manual for the manufacturer's specific recommendation. 
This video explains when to change spark plugs and what happens if you don't: 1mHonest Mechanic ColoradoYouTube · Dec 24, 2023
Why it's important

• Engine performance: Spark plugs that are past their prime can cause rough idling, poor acceleration, and decreased fuel efficiency. 
• Preventing damage: Over time, worn-out plugs can put extra stress on other components, like ignition coils, and may seize in the engine block, making them harder to remove later. 
• Preventative maintenance: Replacing spark plugs is a form of preventative maintenance that can prevent more costly repairs down the line. 

This video explains why it's important to change spark plugs at 100k miles: 52sWhite One Auto, LLCYouTube · May 19, 2021
What to consider

• Owner's manual: Your vehicle's owner's manual is the most reliable source for the correct replacement interval and recommended plug type. 
• Spark plug type: The lifespan of spark plugs varies by material. Iridium plugs are often rated for 100,000 miles or more, while other types like copper or platinum have shorter lifespans. 
• Driving conditions: Severe driving conditions can shorten the life of spark plugs, so your interval may be shorter than recommended if you frequently tow, drive in extreme temperatures, or frequently start and stop. 

What year to stay away from Lexus RX 350?

Years to avoid for the Lexus RX 350 include 2007, 2008, 2010, 2016, and 2017 due to common problems like oil leaks, engine issues, brake failures, and faulty sensors. The 2010-2012 models are particularly prone to a ruptured oil cooler line that can cause engine failure, while the 2007-2009 models had issues with cracking dashboards and a faulty brake master cylinder. The 2016 and 2017 models saw recalls related to airbags and issues with rain sensors, notes CoPilot.
 
You can watch this video to learn about the history of the Lexus RX 350 and common problems in different generations: 1mThe Miles DrivenYouTube · Dec 22, 2024
Years to avoid and why

• 2007–2009: These models are known for cracking dashboards and a faulty brake master cylinder that can lead to brake failure. 
• 2010–2012: A common and severe problem with these years is the oil cooler line, which can rupture and lead to engine failure. 
• 2016–2017: The 2016 model year had airbag recalls and was the first year of a new generation, which can lead to early bugs. The 2017 model had issues with the rain sensor and wipers, in addition to having its own airbag recalls. 

What to look for instead

• 2011–2015: These models generally have fewer issues, with the 2013–2015 models in particular being noted as more reliable. 
• 2018–2022: Models from these years are considered more reliable, especially those with the redesigned exterior. 
• 2020–2022: These are considered among the most reliable years, with the 2020 model year being a good choice. 

This video discusses the best Lexus RX 350 years to buy: 59sThe Miles DrivenYouTube · Dec 18, 2024

How often should spark plugs be changed on a Lexus RX 350?

120,000 Miles – While this may seem like a bit of a gap, everything in between 50,000 miles and 120,000 miles is just repeated services. However, at this point, you'll want to have your spark plugs replaced. 150,000 Miles – At this service interval, you'll need a variety of repeated services completed.

How much does it cost to replace spark plugs in a RX350?

The cost to replace the spark plugs in a Lexus RX 350 typically ranges from approximately $575 to over $1,600, depending on the model year and where the service is performed. While some sources estimate the cost between $575 and $800, higher estimates can reach $1,600 due to labor, especially since accessing the spark plugs can be challenging on these vehicles. 
Cost breakdown

• Average cost: Many estimate a price between $575 and $800 for the service. 
• Dealer/shop price: Prices at a dealer or shop can range from about $725 to over $1,630, with older models like the 2010 RX 350 often being on the higher end. 
• Part cost: The price for individual spark plugs is relatively low, around $10 each, but labor significantly increases the total cost. 
• Labor cost: The higher price is mainly due to the complex labor required to access the spark plugs, which involves removing several engine parts. 

Factors that affect cost

• Model year: Newer models may have slightly lower costs, while older ones can be more expensive. 
• Location: Prices vary depending on the shop or dealership and your geographic location. 
• Additional services: The total price can increase if other services are recommended at the same time.