(This may be a re-post but I can't remember any replies) Are there any consequenses of spraying carb cleaner inside the top of the fuel injection system (without air cleaner)with the engine running? I noticed for the first time today I have black build-up (which has only recently started) inside the intake and on the diaphragm entering the system. I warmed the engine and sprayed a spray-style carb cleaner into the top while running the engine around 2000 RPM. It belches a horribly poisonous smelling cloud when you do this. Will this spray-style carb cleaner harm the engine, exhaust, catalytic converter, or especially the O2 sensor? I just had a new O2 sensor installed and I don't want to ruin it. Anyone? Is there a different recommendation? Or can I do this safely? Chris #3876