i bought another toyota starlet. its 1987 having 1E. its just for taking me around. i have it here in newzealand. today i open the air box and had a look to the air filter, it was burnt a little like a coin size, y is that. also it stalls two three times when i start it like in morning or 2-3 hrs kai baad. can u plz tell wat is it and wat has to be done.