ok , Brake clean was not a good choice for cleaning your afm mate, its a sensor that measures the amount of air rushing past it thus turning that into a voltage to send a signal to the computer to tell the engine how much air its getting.
SO , if you have damaged it by cleaning it then the signal could be wrong , thus telling the computer the wrong info, so the computer adjusts naturally and so now its prolly got the wrong info for starting and when it idles its really rich as the computer has no idea how much air its really getting.
do you have a r32 gtr or what ? cause you should have 2 x air flow meters. if its a 32 gtst only one ?
i believe this is prolly your problem and i maybe able to source a second hand one to test if thats the cause, otherwise dude you are looking anything up to $700 for new ones , im not sure tho will get back to you. I'll ask my local supplier RBNT ...... lol
cheers
Ron