I got issues!
No 1), it's not supposed to open in neutral/park. That's your problem right there! When it opens, it sends a huge fuel dump into the manifold. And then it is practically flooded. Of course it will want to die when you back out of the throttle.
Now go tighten that thing up!
No 2),12/36@ 3500 is pretty close.At least close enough, that we don't have to worry about it being over-advanced and wanting to detonate itself to death.