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Torque Your Toyota’s Spark Plugs the Right Way Without a Torque Wrench

Here’s a useful demonstration on how to properly torque spark plugs and avoid a costly damage mistake from poor technique. Plus, a new website and blog for DIY car repair enthusiasts and car project builders.


If you have not seen a spark plug service since the days of when it was simply a matter of opening the hood and reaching each spark plug with a deep socket and ratchet extension bar, then here is a good-to-know how-to demo of servicing modern car spark plugs using a 2015 Prius with 105,000 miles on it as an example, courtesy of the Toyota Maintenance YouTube channel.

Related article: Ford F-150 EcoBoost Spark Plug Replacement Demo

Spark Plug Servicing

Spark plug servicing is one of the more common service jobs you will need to eventually have done to your car (or do it yourself should you decide this is a task you can handle) when your vehicle maintenance manual tells you it is time to have this service done.

However, it is also possible that you may need to have spark plug servicing done before the recommended maintenance period. Sparks plugs can go prematurely bad, or other conditions within the engine may develop that lead to fouling the spark plugs with gas, oil, and/or carbon deposits which will interfere with the spark from the spark plug electrodes that ignites the vaporized fuel in a cylinder.

Symptoms of a bad spark plug problem can include:

• Hard starts
• Engine misfires
• Rough idling
• Reduced gas mileage
• Lack of acceleration

In an earlier article, we learned how to do spark plug replacement on a Lexus and discovered there is a good reason why this can be a $400 service at a dealership garage---it takes a significant amount of engine disassembly to get to the spark plugs before they can be removed along with their spark coil.

The good news is that it is not always that difficult.

Follow along with Peter as he shows how it is done on a 2015 Prius with a special focus on achieving the correct torque on the spark plugs.

The Value of This Video

The value of this recommended video is that it explains what happens when spark plugs during servicing are tightened too loose or too tight, can lead to problems that includes the need for an expensive repair afterward to fix the mistake. Plus, how to torque a spark plug without an expensive torque wrench and why this is especially important for newer engines with aluminum heads.

How To Properly Torque Spark Plugs

For additional articles related to spark plugs, here are a few for your consideration:


Announcing: A new website and blog for DIY car repair enthusiasts and car project builders

If you are interested and new to learning how to go about a car project rebuild and/or restoration---or how to get started on DIY car repairs---here is a new website and blog I have recently created that will cover both desires from my “Zen and the Art of DIY Car Repair” website that has a focus on a different approach to learning how to become your own mechanic.

For now, the home page is titled “The Zen of Rebuilding a 1973 Ford F-100 Truck” as an intro example of what I experienced during a rebuild that is continuing today with a focus on not just one, but several methods I believe will prove beneficial to anyone regardless of their automotive skills and education to become a better and more successful DIY mechanic.

For now, the content is limited with the first two blog posts, but be assured it will grow and so will your skills over time.

Timothy Boyer is an automotive reporter based in Cincinnati. Experienced with early car restorations, he regularly restores older vehicles with engine modifications for improved performance. Follow Tim on  “Zen and the Art of DIY Car Repair” website, the Zen Mechanic blog and Twitter at @TimBoyerWrites for daily news and topics related to new and used cars and trucks.

COMING UP NEXT: The Truth About Aftermarket Brake Pads Warning

Image source: Deposit Photos