Misfires, loss of power. I did the plugs and coils, with some improvement.

I found out about the ECU training procedure, and it helped quite a bit after the change. I believe that this ECU procedure should be done every time you ECU loses power - battery changes, disconnecting the battery, etc., Or "fixing" something

My car actually prompts during the procedure, counting down the time. If you don't do it, an ECU reset can mess up timing, etc., and the ECU will take it's time trying things based on it's current data

Anyhow, I'm still having problems. Lots of miles, and I haven't done the valve adjustment, which probable should be next.

But are there sensors to work on that could be causing the problem? And should I be worrying about the fuel filter? What are the symptoms of a clogged fuel filter? I'm still getting lots of power at full throttle. What should I do next?

 

Get the valves adjusted first.

 

Re-check your plug/coils job
I have a feeling that you got counterfeit coils (unless you bought them from official Hitachi distributor)

 

Good point J, there are tons of cheap junk coils out there. If you didn't go with OEM or Hitachis (the same thing except OEMs are marked up), definitely fix that first.

Here's what you want (buy 4):