I have a 2000 gs-r thats pretty much stock besides a short ram intake and a test pipe instead of a catalytic converter with shorty exhaust. Its stock integra exhaust manifold and stock piping that dumps straight down where the second bend to the side of the fuel tank is. On warm up and only on warm up i get what is described in title on the ground below the exhaust. It completely stops once the coolant temp gauge starts to register within the C and H. Should this be happening? If not im thinkin its the coolant temp sensor. I have replaced a bunch of stuff since buying the car about 3 weeks ago. I put a short ram with a k&n on it instead of the stock intake pipe that had a shit Spectre filter(autozone k&n knock off) i have replaced the o2 sensors (car lacked a rear o2, added a rear o2 with a cheater that removed CEL), MAP sensor, TPS, IAT, fuel filter, fuel injectors, cleaned the iac valve, timing belt with tensioner, water pump, and properly adjusted the valves within honda recommended cold lash. the car runs great otherwise and after i replaced all this it doesnt miss, hesitate, sputter, or smell like its running rich except when cold. Either way i plan on replacing the coolant temp sensor within a week.