Well guys, here’s an update. I bought a water pump + timing belt kit that also include an idle pulley and tensioner and I did it myself following all the instructions on the service manual. Everything was installed by torque specs <3
Guess what… the problem is gone. No more misfires or Check engine lights. Car runs like new.
I want to thanks all of you for your comments and support. I hope someone else googling the same issue can resolve its car problem with this looong thread.
BTW… this was the hardest part. 120 lbs torque.
