in swapping my ZC into a '91 Si, I have noted the lack of a fast idle control solenoid valve on the ZC's intake manifold.
according to my manual, this valve kicks in at -10° for super cold ambient driving. Does anyone know how to
deal with the lack of this device on a ZC? I am going to leave the two wires (blue & blk/yellow)unconnected for now,
and hopefully it won't give me an annoying error code. As well, vacuum line #12; can anyone suggest a suitable source
on the ZC? The HASports site tells to "tee it into the idle up diaphrams hose"; I cannot locate this on any of my manual's schematics.

I have checked all the references to this topic in the archives, and still cannot find the info I need, so any solutions very
much appreciated!

 

Check some ZC Install sites, Just go to google and search for ZC engine install, they'll tell you what to do with those wires, also there is one vaccuum line that does not get used, you need to block it off with a screw or something.

 

I know for sure that you don't need the fast idle solenoid at all. I swapped out my '90 Si intake manifold for a D16Y8 manifold - it doesn't have a fast idle solenoid. By completely disconnecting it from the wiring harness, you wont get any error codes, and you will have no idle problems.

As for vacuum hose #12, I honestly don't know where it's supposed to go. I have heard that with ZC swaps, you will always have 1 hose that can't go anywhere (if the ZC is a manual, vs. 2 extra hoses with an auto ZC), so either you could tee it into another vacuum hose, or just plug it up. You shouldn't have any problems, but then again, I haven't done a ZC swap.....

Good Luck!

 

it dont do ****!!!!!!! theres not even a code for the dam thing!!!!!!!!

 

It will bounce a little, well mine does anyway. But I've also been told ZCs tend to idle high when cold, and low when hot. More so than the stock Si.