I just put in a sohc ZC in my 91 Si and have run into a small problem. The rear of the intake mani is a little different than on the original engine I took out. There is a sensor with 2 wires coming out on the original mani that I can't reinstall on the new engine. I believe it is the fast idle solenoid/valve assembly. The ZC obviously ran fine without it in japan so do I need it in my car? Will I throw a code for not having it hooked up? If it will run as normal and get just as good gas milage I'd rather leave it as is. Of course I'll swap manifolds if I have to. It's the sensor on the far left with 2 wires out of the bottom and a vacuum line on it's right. In the bottom pic (ZC), It doesn't look like it's needed. Thanks for your help!






Modified by ktp1598 at 6:11 AM 7/8/2008


Modified by ktp1598 at 6:16 PM 7/25/2008

 

I'm back from vacation and need to get this running. I'd like to have it running in a day or 2, so please help if you can! Thanks,
Bobby

 

Which manifold are you talking about swapping the top picture or the bottom picture? I have a 1990 crx si with a SOHC ZC and it has the same manifold as the one shown in your top picture and it runs great. It must be the original one for the car on the usdm model I am assuming. The zc engine should run fine with the intake manifold that is shown in the top picture. I wouldn't eliminate any sensors cause you will throw a check engine light.

 

just leave the Fast Idle Control Valve connecter not connected - it doesn't need it to run correctly - does not throw check engine light - the FICV just boosts the idle slightly when air temp is below -10C (14F) - other than that it does nothing