Sea foam does a pretty good job. You might want to do it couple of time to be sure that you got as much as you can. I have to agree that upper intake will be a little hard to "clean". It could be taken off and you could have a hot soak done on it. Which is basically a bath for your parts. You are going to want to get the sea foam into your system as close to the TB as possible. This will allow the sea foam to follow the air path and get to where it needs to go. Kind of cup a vac. line in your hands and SLOWLY pour the sea foam in the vac line will suck it right up. I say slowly cause you don't want to hydo lock your motor. Once you get about 2/3 to a whole can in there shut it down. Drink a beer maybe two or three. How ever many you can drink in an hour. Then start it up. It might not start right up but, keep turning it over til it does. It will idle like crap and smoke like crazzzzyy. Take it out for a spin @ ~3500RPM for 3-5 min. Use a low gear and drive it or just lay on the gas. Trick is to get it good and hot to break off any dirt carbon, or any thing else you may have suck up in the last "18 MONTHS". You might even want to do this again but it should suffice.
Oh crap... I almost forgot. Before you do any of this,.....
MAKE SURE YOUR AIR FILTER IS IN PLACE!!!!! LMAO
Later Dude,
Jeff
