rowan2•12d ago

I used to think all spark plugs were basically the same until my engine started misfiring on I-94

3 comments

3 Comments

Copper plugs are fine for old trucks but modern engines need iridium. I learned that the hard way after three days of chasing a misfire on my 2015 Civic. Just changed all four and it runs like new again.

price.tara12d ago

My 2012 Corolla has 180k miles on plain old copper plugs and it starts on the first crank every single time. I change them every 30k miles like the manual says and it runs smooth. Is it possible your misfire was from something else like a bad coil pack or dirty injector? Those modern plugs are expensive and sometimes people swap parts instead of finding the real problem. I've seen a lot of guys chase misfires for days only to find a vacuum leak or a bad ground wire. What made you so sure it was the plugs and not the ignition coils?

danielmason12d ago

Hold on, only four spark plugs? My 2015 Civic has a four cylinder engine so that makes sense, but wait you only had four spark plugs total? I just realized my 2015 Civic actually has an I4 too, but I remember reading somewhere they started putting turbo fours in those newer ones and it blew my mind. Four cylinders with a turbo, that is crazy to me. I guess I just never thought about it being that small of an engine.