I've got a 90 GT and latley i have been noticing a few little problems. My car seems to idol really funny when i start it. it will surge between about 400-1200 rpm and then die. its very sparatic though, and it will also die when im driving if i put the clutch in. It seems to be worse if the defrost or the A/c is on. additionaly, my car has been spitting out a little smoke when i get it into the higher RPM range. if i really get on it, a pretty sizable cloud will come out. it looks to be white so i dont think its oil. any ideas?