Hi guys... I have a problem with my 1996 Honda civic. In the early morning, I start the engine when it's idle looks allright but when I drive it rev fluctuate like people breathing lol but when the engine get hotter like I drive it for almost 40 mnts the rev not fluctuate again. The rev fluctuate only when the engine a little bit cold. Can anyone helping me please..
Thanks in advance guys.
Cheers.:D

. Clean the Idle Air Control Valve (IACV):

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-7.html#post1054149

. Clean throttle plate, upper & lower ports, and throttle body.

. Clean air box and replace air filter.