Last couple of weks ago, i had my alternator change due to that its not charging anymore, the alternator i replace is the exact model and type, after installing it, 1 click and car starts fine, then after couple of minutes driving, i notice that when i turn the a/c on while in full stop, everything is fine, but when i rev it and pass 1000 rpm and release the gas pedal the rpm goes down to 600 and it stays there for like 5 secs. Then it goes back up by itself.. But if am not use the a/c everything is ok.
We already check the voltage of the alternator and its giving out the right voltage, we use a digital reader and its normal with and without load.
My main issue here is why when i rev it then release it right away the rpm goes 600 and it stays there for 5 secs and back to normal.
Is this time to clean the throttle body and intake and all sensor?
Hope somebody here can help me out
ride is 1999-2000 civic manual 1.6 vtec engine