Someone PLEASE HELP!!! When I start my Civic.. It revs high for like 5 seconds then revs up and down.. WTF What do I do to fix this !!

 

Does the issue go away once the car is warmed up?

First thing to do would be to remove the IAC and clean it out since that controls the idle.

 

^^^ clean idle air control valve

also try this after your car has been sitting overnight so it's cool. Turn your car on, spray some brake cleaner around every vacuum line, seal you can find. If your engine hesitates at any point go back to that spot, spray some more and check.

replace any bad lines/gaskets.

 

So i replaced the IACV.. No more Idle revving up and down.. thanks for the Advice guys !

 

Sick! Glad to hear this was resolved.