ive only had my truck (nitro rustler 2.5) for about 3 weeks. ive been tearing the hell out of it, but thats been a chance to upgrade to aluminum arms, carbon towers, ect. now the engines acting weird. it started dying when i applied throttle and idles really weak(kind of like a weed whacker sound, all "puttery"). somebody told me it sounds like an air leak and to seal the engine. no help. now the thing idles for about 10 seconds (still "puttery") then dies. all the engine/carb is still stock and traxxas makes it a point in the manual to not give an intelligent person any advice (pull trigger=make car go, thats about it). any advice would be much appreciated. also, if you have any good tuning or upgrade tips, please include them.