2000 S80 Surges at 45mph after Xemodex ETM?

[c21no1]

I just installed a Xemodex ETM in my 2000 S80, I don't have the dead throttle anymore, but I still have a surge around 45-50mph, my cruise control still doesn't work sometimes and the Check Engine light is back on, I have to get the codes yet. I was told that the last time the codes were scanned, that it may be a faulty gas cap, but after researching here it sounded more like a faulty emissions hose? Any help would be greatly appreciated!