My 2004 Fx4 has been having some vibrations and power problems. I get a flashing engine light at times then goes away. I've tried reading OBD codes (granted a few days later) but it did not give me any codes. Is there a way to retrieve those codes and determine what is going on and where to focus my efforts? For reference, ~120k miles, plugs were replaced at 100k, but wonder if they could be the problem. Also wonder about coils but what else could be causing this?

 

My truck did this but mine showed a misfire code. Come to find out had a valve go down