So it recognizes the cart and will bring up a list of codes?
If that is the case and Powersaves was bringing up codes for Mario Kart before and now it isn't, you problem (whether you want to believe it or not) is your internet connection. The reason why I'm confident that this is your problem is two-fold.
1. Pokemon (a card 2 game) will not recognize and keeps cycling.
2. Mario Kart (a card 1 game that was once being recognized and getting codes from the database) cannot connect to the servers and retrieve codes. It is instead defaulting to only the save/restore functions.
That is the only plausible explanation. I also have high speed internet and VOIP. I once had an issue that caused signal degradation that would allow for the services to work, but the signal was degrading. This first manifested as people not being able to hear me on a phone while I could hear them. The signal continued to degrade and began effecting the internet (which is how I tracked it to my side.) It required several service calls to fix my problem and ultimately led back to a distro box for my block. I'm not saying that is what is causing your internet issues, but am just illustrating that just because you have high speed internet that seems like it's working doesn't mean that it never goes down.
