93 honda prelude idle?

i have 93 honda prelude and when i cold start it, its start and goes to 2,000 rmp for 15 sec then up down up down and when it warms up it will only idle if you help it find the idle like you have to ease off the gas slowly but if you floor it and get off then it dies or has the surges help, btw just did the swap and new tps