Why don't you take it to a gundoc? For strange problems like this, the internet isn't exactly the best medium to diagnose a gun. A gundoc in person could help you a lot more.

because i didnt know any gundoc at mtl...

Could it be the pistonhead ?
because i m just dissassembly eveything and some pieces are interverted.

https://dl.dropbox.com/sh/t7v903ysu0...1/CIMG0050.JPG

https://dl-web.dropbox.com/get/Publi...JPG?w=ab409266

https://dl-web.dropbox.com/get/Publi...JPG?w=a35da568

https://dl-web.dropbox.com/get/Publi...JPG?w=6c95bf38
https://dl-web.dropbox.com/get/Publi...JPG?w=9942cfb7

https://dl-web.dropbox.com/get/Publi...JPG?w=188b3e63

https://dl-web.dropbox.com/get/Publi...JPG?w=058ce0e0

https://dl-web.dropbox.com/get/Publi...JPG?w=1ad2ed46

https://dl-web.dropbox.com/get/Publi...JPG?w=b3a57e5b

https://dl-web.dropbox.com/get/Publi...JPG?w=2c2c3dff

So send it to someone outside Montreal then.

Also have you looked here?
http://airsoftcanada.com/showthread.php?t=72809

ok, it will be my last call before keeping it for pieces and buying a new one marui in a year or two... But understand that im a toy designer and prototype maker, and airsoft is my hobby since 6 year, i take this gun to be my '' frankenstein'' because p90 are easy to take appart, but if i really see that i'm going nowhere, yeah im gonna take my money and call somebody else.

it a good practice for me, i just need a little push =) !

It's good to try to tinker yourself, but if you don't know what to look for from experience it isn't going to help.

Its why im here, with my pictures =).

Like I said, in person is much different than on the internet. Problems that are solved in hours/days/weeks on here might be something that a gundoc could diagnose in a couple minutes or an hour in person.

By the way, there are gundocs in Montreal... most are just not listed on the "official" list since on one updated it in years.

For example, I am doing some work from my team and people I know.

I knows ''ninja en short'' but i he didnt looks interested by v6.
Kos-Mos if you feel any interest dont hesitate my p90 wait for too long to shootsomething else that air... =)

still the issue.

Looks like you have a bad nozzle... Deepfire is not exactly known for good parts...

If I where you, I would reinstall all the stock parts and try again. It might also be a torn hop-up rubber.

your dropbox links don't work.

i have encountered the same issue, tried 3 different nozzles, only piece that hasnt been changed is the hop up itself, one thankfully is coming in tomorrow with a second factory gearbox. but all started with the gears so i would say the sector post is the issue not pulling the tappet back far enough, original has an enlarged post for that reason likely.