my friend recently dropped a b16 in to his 89 crx hf he had that problem when he put it on reverse the idle would go crazy but thanks to the people in honda-tech the problem was solved by cutting the b9 wire off .
there's a new problem when we have the fan or the heater on the car idles fine but at soon as we turn it off the idle gets crazy going up to 2000 and down any body ever had this problem help

 

it sounds like you have a IAC problem