Yeah it has an EFI and they used a power washer. It is under warranty and so far they havent charged me for anything including oil.
This was my first thought too, some kind of short in the EFI, as it happened right after they washed it had been feeling a bit ill just before this too.

I might have found the problem though on my own. or at least another problem. Last night while i was installing a USB charge i found a small hole in a tube coming from the gas tank. Its not the main gas line and nothing seems to be coming out of it so i don't really know what it's for. The hole is located right next to the gas tank and... how do i describe this... it was ripped by the nipple coming from the tank. The tube probably doesn't have enough slack. I was able to reposition the tube so the hole was effectively smaller. This might explain why it worked better for a little while after i took it to the shop last time as they removed the tank and may have accidentally moved the hole.

I also noticed a loose and stripped screw holding the section just after the air filter to the frame. That could explain the rattling. This is the 4rd stripped screw ive found. Another fell out of the chain guide and the other two i probably caused...

I'll take it back to the shop today and let you know what happens.

By the way, I also tried installing a pair of those cheap acerbis hand guards from taobao and they don't fit. They don't go all the way around the strange break fluid reservoir.