Hello,
You probably have oil in the spark plugs. Is the spark plug covered with "dark" fluid?
Usually if there is a leak in the valve cover gasket, oil can leak into the plugs.
Are there any trouble codes?
https://youtu.be/ahK_eucFi-k
Here is an article you might find helpful:
'
https://www.2carpros.com/articles/how-to-tune-up-a-car-engine
https://youtu.be/9M6xWMMRe0E
I have attached spark plug replacement as well and valve cover gasket replacement.
Let me know if you have any questions.
Thank you.
Images (Click to enlarge)
Jul 14, 2021 at 1:01 PM