i have a 97 civic hatch wtiha d16y7...well this morning i started it up and it started ti idle at 1500 then went down to 500 and sounded like it was about to die then came back up to 1500 this happened 3 times...i was just wondering if this has happened to someone else and what was the problem

 

check the fast idle valve(sensor) or the IAC sensor i had an IAC go out on my 99si and it did something similar to that

 

clean your IACV.