OK a few months ago I got my car back from topspeed from getting tuned. I was looking in the engine bay and noticed this sensor sitting there and didn't know what it was for and why one of the nipples was disconnected, so I called topspeed and they said it had something to do with emissions and that they delete it, so I took it as I could unplug it and that would be it. Well I threw this code after I did that P0457 (evaporative emission system leak /fuel cap loose /off ) I hooked the sensor back up and cleared the code. It came back and keeps coming back. I called topspeed again and they told me to replace the gas cap, do I did, cleared the code and it came back. I'm at a dead end. Does any one know what could be going on here and if it's this sensor or something else. Thanks!