Toyota-Lexus-Subaru-Honda Spark Plugs and Ignition System

When I first started working as a mechanic I kept hearing older technicians say that it was important to use factory ignition parts in general, and factory spark plugs included in that.

My first take on this was that it was probably just a case of mechanic superstition-I thought surely any manufacturer in the industry could make good spark plugs.

Over the years, however, I’ve seen too many instances where people have gone from shop to shop spending hundreds of dollars trying to fix a drivability problem “that couldn’t be due to the spark plugs or the rest the ignition system because all of that was new,” and yet the problem would trace exactly to those aftermarket parts and be resolved with the installation of factory, original Toyota supplier parts.