Weird spots on piston and plug color. help!? | 2015+ S550 Mustang Forum (GT, EcoBoost, GT350, GT500, Bullitt, Mach 1) - Mustang6G.com
Removed some ''old'' rusty spark plugs from my Reatta with 62k miles - Buick Reatta - Antique Automobile Club of America - Discussion Forums
![Spark plug on my 2.4 accord. They are Iridium plugs and not even 2 years old. Why are they rusty? Not loosing coolant and plenty of oil. Just replaced valve cover gasket Spark plug on my 2.4 accord. They are Iridium plugs and not even 2 years old. Why are they rusty? Not loosing coolant and plenty of oil. Just replaced valve cover gasket](https://preview.redd.it/enwl5wpf0bk81.jpg?auto=webp&s=eb9cc9fb7bd552f1cf5ace480525c5bcb42bba11)