Hello everyone. I have a 2004 Honda Accord V6 EX that I've owned for 2 years.
3 months after I bought it, the check engine light came on.... Two days later, it turned off. Since then, it started happening every once in a while ( On and Off)
The engine started vibrating in idle... and now it vibrates a lot and it is very noticeable.

I did the major maintenance for it ( changed spark plugs, flush all fluids) recently, and nothing changed.

A couple days ago, I decided to change the intake filter, since I never checked it...... pulled that open.... and there was NO FILTER!!!!!
I took it to friend of mine to check if it has any error codes, and it showed that I have misfire in all cylinders!!

Do you think that caused all these problems, and what should I do??!!

Thank you