Now that I have tuned it up, replaced the air cleaner and the MFS sensor as well as cleaned the EGR. I've encountered another problem.
Today on the way to Springfield with the A/C on, it started doing that surging or over revving sound AGAIN. Man just when I thought I had it fixed.
The sound doesn't seem to effect the performance but I don't know what else could be wrong.
Could it be the PCV valve? The throttle body needs cleaning? Need some help on this.
On a good note, the check engine light is off and I have regained my power.