Well here's the situation my spedometer stopped working and the car slips in and out of Limp Mode at will also sometimes the spedometer comes back on intermitantly when it feels like it could this be an engine speed sensor?

 

You're going to have to call your tuner to get some help.

 

Speed sensor is a good guess.
Swap with a buddy if you can to know for sure, or if you can find the specs you can test it with a multi-meter.
Might not be to easy to get to the sensor though, I think its on top the tranny.