Thank you coolnorthsound and all the other replies, every little bit helps. I have checked the system pretty thoroughly now and this is what i best believe. The machine gets fuel(carbs cleaned, new lines, cleaned fuel pump, new fuel filter) The spark plugs are new but seem to foul really easy, i also notice generallly that it struggles after it warms up. I think its possible that i may have a small leak in the crank seal(although nothin, no fluids drip out) and maybe my coils are bad. Since coils are a relatively easy fix i have ordered some to replace. I also had my muffler rebuilt and therefore i know the exhaust system works fine. I have run it without the air box as well but no better results occured. i have the owners manual(sucks) and the bombardier shop manual(also sucks) and the MIC carb manual(really sucks) I have to do the work myself to save money, learn, and mostly there are no ski-doo dealers within 100miles of my home. So i will deffinately look into the clymer shop manual. Now, i did most of these diagnosis and so forth with the machine on blocks, but today(got 3inch of snow) i ran it, it iddled like a champ, putz at around 10mph pretty good, but could never get into second gear. I now wonder if that means i have a clutch problem, or if the engine doesnt produce enough power to get it into high gear. Also, i have messed with some of the carb setttings and dont really now what im doin, because the manual sucks. I think i might be runnin a little or a lot to rich, but i dont know, i think this because the plugs foul so easily, or at least they dont fire all the time(part of the reason why im gonna change the coils). I Have the SS model by the way.(377 2cylnder) What do i need to do a compression test? If i have bad compression what does that mean, how do i fix that, is it expensive? By the way, i got this machine three weeks ago and it ran pretty well, stalling out every hour or so, but i had full range of power and speed. It quickly progressively got worse to the now recent point where it hardly moves. Also, it starts cold on the first pull with no problems. Thanks, please respond if you have any ideas, i am new to this and would like to get this thing going!! Thanks, cheers.