Need help with check engine light . . .

1st question: Can I go anywhere to get my ECU trouble codes or where and how can I read the ECU trouble codes?


2nd: I went to TTC using the plastic valves and after 20 minutes of driving the check engine light came on.

So I went back to sequential.

Then I tried it again and the same thing happened so I went back to sequential!

Now I tried the ETTC mod and everything was perfect until after 20 minutes of driving in TTC and/or sequential the check engine light came on again.

Could it be the pressure tank or ( the ehaust by pass valve
which I did not cap off)

I want to leave the check engine light on and see what the trouble code is.

Please anyone experienceing this PITA $hit?

Any suggestions or comments are greatly welcome!