i have a 93 civic lx with a d16y8 that is having a problem with the idle. i was just wondering if the brake booster could cause that? i don't think its the iacv cause i have tryed 2 used ones and 1 brand new one with no change in the idle. one thing i have noticed is that the idle problem seems to go away when my a/c is turned on and is at full blast(a/c has been removed besides anything under the dash). oh one more thing i don't know it this will help but i'm using a d15 intake manifold, d15 injectors and all other sensors on the d15 intake manifold. other than that i'm also running a p28 ecu