I have a 2000 Honda Civic Si wit a B20 vtec swap, B16 head, and when the car is idling, the rpm's will rise up a little then go back down, at a slow pace, and after a while, it will go back down to a 1000, and when i rev it a little it will start again. When it starts, its idling at 1500 when it does it, and i have actually seen it happen at a 1000 one time.
Now i have checked all hoses to the intake manifold and every thing is tightly put in, all sensors are plugged in, and the engine light is not on, so i have no idea what it is.
PLEASE i need some help!!!