HI everyone im in the middle of doing a mini me head swap from a d16y7 to a y8 setup. The thing is when i start up the car the car idles up and down from 2500k down to around 1500k. Now i heard that there is a diffrence between the manual y8 IM and TB from the auto y8 IM and TB. this all has to relate to the IAVC that is mounted in diffrent locations and is a two mail outlet instead of a three. i need to know if it is because that would mean i would have to put on the right IM and i don't want to buy a new one with out a certain answer. I just want my car back lol. Thanks boyz

 

Is the car revving from 0-2500? If it is you could have a simple vac leak or a leaky intake manifold gasket. I would try spraying carb cleaner around the vac lines and intake mani gasket to see if the engine boggs down, because if it does, you have just located a leak. I always try the easiest/cheapest fixes first.

 

when you first start if up it jumps up to 2000 then rises to 2500 then falls to 1500 and keeps jumping between the two like someone is pushing on and off the gas and i checked everything and couldnt find a leak..its being a pain..

 

There must be a leak. Also it could be that the throttle cable is too tight and it's holding the throttle plate partway open.

 

i have the same problem right now. Ive done everything i can think of. No leaks all hoses are good timing is on too. It just idles up and down while in park but when its in gear it idles fine. I pulled off the IACV sensor while its on and it idles down. but then wont idle right when i come to a stop. I think it might have to do with my computer. Did u get the right computer for the mini me swap. If i remember right its a P28 ecu. As for wat causes thuis im at my wits end and i think i will just leave it idling up and down since it only does it in park.

 

If you pull the plug off the IACV with the engine warmed up, it should idle so low that it almost stalls, about 400 rpm (but don't trust the dash tach to read that correctly). If it still idles higher than that with the IACV disconnected try turning the air screw on the top of the throttle body. Don't mess with the lever stop screw on the side of the throttle body. If idleing too fast, the ECU will cut power to the IACV entirely, once it has done that if there is still extra air coming in it will idle too high.

 

i have the right computer for a ex manual checked but i just looked at a pic online that shows IAVC valve for a manual civic ex on the back of the intake manifold with only a two male outlet. Now i think the problem is that mine is frim a auto ex because IAVC is located on the bottom of the TB and has a three male outlet. Could this be causing all of my headaches???????? And trust me i looked up and down with several mechanics for a leak and there was none lol

 

ok well i have the idle screw all the way in and it does idle about 420 with the iacv disconnected, but when i plug it back in it does its **** again. I have already replaced the iacv and they both do the same thing. anymore advice

 

as for too much air there is barely any air being sucked in now

 

Just a thought. In these cases, moderator mxs has suggested bleeding the cooling system to remove possible air bubbles, which can cause aberrant fluctuations in coolant temperature readings by the IACV and ECT sensor.