A Guide to Spark Plug Replacement for the 2017-2022 Lexus RX350
Keep your RX350's V6 engine running strong by choosing the right spark plugs and knowing when to change them.
- The correct service interval for spark plugs on a 2017-2022 RX350 is 60,000 miles.
- Use only high-quality Iridium spark plugs from OEM-equivalent brands like Denso or NGK for best results.
- Replacement of the three rear spark plugs is difficult and requires removing the intake manifold, which is why labor costs are high.
- There are no specific recalls or TSBs for spark plugs on this model; they are a standard maintenance item.
Is Your RX350 Telling You It's Time for New Spark Plugs?
Worn-out spark plugs can cause noticeable problems. Because they are a normal wear item, they need to be replaced as part of your vehicle's scheduled maintenance. The first signs of trouble often appear as a decrease in engine performance. Paying attention to these symptoms can prevent further issues down the road.
Common Symptoms of Failing Spark Plugs:
🎬 Watch: A visual guide to common symptoms of bad spark plugs.- Rough Idling: Your engine may shake or sound uneven when you're stopped.
- Poor Acceleration: The vehicle may feel sluggish or slow to respond when you press the gas pedal.
- Reduced Fuel Economy: You might notice you're visiting the gas station more often.
- Engine Misfires: You may feel a hesitation or stumble from the engine while driving. This can cause the Check Engine Light to flash.
- Difficulty Starting: The engine may take longer than usual to turn over and start.
Check Engine Light Codes
A common code for failing spark plugs is P0300 (Random/Multiple Cylinder Misfire). This general code is often joined by more specific codes, like P0301 through P0306, which tell you exactly which of the six cylinders is misfiring. Worn spark plugs are a very frequent cause of these codes.
Choosing the Right Aftermarket Spark Plugs
Your Lexus RX350 came from the factory with high-quality, long-lasting iridium spark plugs, typically made by Denso or NGK. When shopping for aftermarket replacements, you have several choices. For this vehicle, it is highly recommended to stick with iridium plugs to maintain original performance and longevity.
Brand Quality Tiers
- Tier 1: OEM-Equivalent (Denso, NGK): These brands are the original equipment manufacturers for Lexus. Choosing an iridium plug from Denso or NGK is the safest bet for guaranteed compatibility, performance, and lifespan. They are often the exact same part as the one from the dealer, just in a different box.
- Tier 2: Reputable Aftermarket (Autolite, Champion): These brands also produce iridium spark plugs that are compatible with your RX350. They can be a good value, but they are not the original supplier for your vehicle.
- Tier 3: Basic Plugs (Copper, Platinum): Some brands offer less expensive copper or platinum plugs. While they might fit, these are considered a downgrade for your RX350's modern engine. They will not last as long as iridium plugs and may reduce performance. The recommended service interval of 60,000 miles is based on using iridium plugs.
A Note on Counterfeits
🎬 See how to spot fake Denso iridium spark plugs before installing.Because Denso and NGK plugs are so popular, counterfeit versions exist, especially on online marketplaces. These fake plugs are made from poor materials and can fail quickly, potentially causing engine damage. Always buy from reputable, authorized auto parts retailers to ensure you are getting genuine parts.
Installation & Known Issues
Lexus recommends replacing the spark plugs in your RX350 every 60,000 miles. While some older Lexus models had a longer interval, the 2GR-FKS engine in 2017-2022 models requires this 60k service.
The replacement process is more involved than on many other cars. Your RX350 has a V6 engine, with three spark plugs in the front and three in the back.
- The front three plugs are easy to access and replace.
- The rear three plugs are located underneath the engine's air intake manifold (also called the plenum). To reach them, this large component must be unbolted and moved out of the way. 🎬 Watch this step-by-step walkthrough of the 2GR-FKS spark plug replacement. This makes the job significantly more difficult and time-consuming.
Because the intake manifold must be removed, it is also recommended to replace the intake manifold and throttle body gaskets at the same time to prevent air leaks. No recalls or Technical Service Bulletins (TSBs) have been issued by Lexus for spark plug failures on this vehicle.
| Item | Estimated Cost |
|---|---|
| Aftermarket Spark Plugs (6 Iridium Plugs) | $70 - $200 |
| OEM Spark Plugs (6 Plugs) | $90 - $120 |
| Shop Labor | $281 - $412 |
| Total Professional Replacement | $400 - $531 |
Frequently Asked Questions
Do I have to replace all six spark plugs at once?
Yes. Spark plugs wear out at a similar rate. Replacing all six at the same time ensures balanced engine performance and saves you from having to do the labor-intensive job again in the near future.
Should I use anti-seize on the new spark plug threads?
Most modern spark plug manufacturers, including NGK and Denso, apply a special metal plating to their plugs that prevents seizing. They recommend NOT using additional anti-seize compound, as it can act as a lubricant and cause you to over-torque the plugs, potentially damaging the engine's cylinder head.
Do I need to gap the new spark plugs?
No. Iridium spark plugs for your RX350 come pre-gapped from the factory. Attempting to adjust the gap on a fine-wire iridium tip can easily damage it. You should only verify the gap is correct if the box has been dropped or damaged.
Why is the dealer quote so much higher than the average?
The high labor cost comes from the difficulty of accessing the three rear spark plugs, which requires removing the intake manifold. A dealership may quote higher labor rates than an independent shop, and some owners have reported quotes up to $1,000.
Helpful Videos
Technical Specifications
OEM Part Numbers: 90919-01263
Material: Iridium. Recommended Brands: Denso, NGK. Quantity Required: 6. Spark Plug Torque: 13 lb-ft. Ignition Coil Bolt Torque: 7 lb-ft.
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The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Lexus RX350: