rev up and down in park

idle air control valve should be on the back of your intake manifold with 2 wires going to it and 2 coolant lines.

Thank you Takoda!!! Most helpfull!

no problem

same thing happened to me... either a bad IAC or a dirty intake manifold...or probably a vaccum issue?

Thank you Anthony! I will check both!

does this make your valves to burn up. i have the same problem when in neutral at a stop it rev's up and down. and i have a valve tapping but my oil level is fine.

I have a 1998 Honda civic lx. Replaced the distributor and the next day my car started acting crazy like having trouble starting it, draining my battery, engine would shake or kick and my rpm is tweaking moving up n down really fast. When I try to rev it, it would have a lag or it will die out. Eventually starting it a couple more times and letting the engine warm up at about 2 or 3000 rpm car would be normal. Only times when I notice these problems is when the engine is cold. Please help thanks

Ok Battery went bad it changed new one then rob up in park to just for a second then I TV goes normal what's wrong can Battery cables cause this yes o rd no I think ones bad