"Over the years I've run into this a lot. Certain plugs just don't work well with certain systems. In many cases the plugs suggested by the manufacture seem to in most cases be the way to go.
It's a whole lot easier to just use what is suggested or what you know worked in the past."
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So true to my experience.10 years ago, I had Pepboy did a tune-up for my car (94 Dodge Intrepid 3.5), and I asked for Platinum plugs, I thought it would be better,paid more for it .
The car did not run as smooth and peppy as it should after tune-up, I thought well the car is 5 years old and over 6ok, may be that's what would eventually happened.
One year later, the engine started having problem, I took it to an individual mechanic who was formerly a tech in one Chrysler dealer, he said one spark wire was bad and one plug was dead, and recommended all wires and plugs be replaced.I went for it.
When working on the car he told me that "I notice you used platinum plug, but this engine was designed to use Champion spark plug which is cheaper and works better, and that might had caused those problem you had".
After the "new" tine up, the car ran so well and I got a speeding ticket on a hilly interstate trip.
using the wrong plug (Platinum in this case) caused me $270. LOL