I have a 2002 civic ex V-TEC 1.7L 4Cyl, manual transmission. I'm having issues for some time now and its getting on my nerve. Whenever I'm in idling mood i noticed that when i press on the gas pedal and released it, the RPM doesn't drop to normal as it should, it stays up for awhile before it actually drop to normal. I found out that the brake booster is sucking in air because when i pinched the hose the idling drops and goes back up when i released it the pliers that i pinched it with. So i change the booster but i still having the same idling issue.i change the idle air control valve to the dealer type but that didn't help. I noticed i have a p0113 code for intake air temperature open circuit and p1505 for pcv valve leakage,i changed the pcv valve for the dealer type as well,inspected the pcv valve hose and no sign of damage,took it to a shop and they didn't find any vacuum leaks,dealer didn't find any leakes they said either. Watch video to see what I'm talking about.