civic and prelude manuals wont be even close. way different beasties.
the carbuerator is probably not working properly. how much do you know about carbs? if you dont know much, then just take it to a shop and tell them what the car is doing. i know those have a gazillion vaccum lines, so some of them may be cracked or broken causing a vaccum leak, which will make the car idle high.
carbs arent the best design, in cold weather like 0 degrees, i dont think there is a carbeurated vehicle on the planet that will start and stay running after the first crank.