Installed new edge Ez since my last one quit working. Now I have a problem where it goes into limp mode after too much boost I think? What’s causing this? Stuck wastegate? 

The engine when you exceed about 20 psi of boost. Sounds like the EZ is not boost fooling. It should. I would contact Edge and see what they say.

Should have said the engine will defuel when 20 or so psi is exceded.