Well first I have a 90 CRX SI with a B16. I have this extra plug "C216" which is Black/Yel - Blu, Now on the helms diagram for the D16 it says it's the dashpot control solenoid while the helms for the B16 says it's a purge cut-off solenoid. So are they the same or is this a typo?

here are some pics to compair the wiring

D16 Dashpot Control Solenoid


B16 Sugre cut-Off Solenoid



Other threads say that this is the Dashpot but it's only vacuum based?


I'm way confused with this plug so please help me out, o yeah my engine idles fine and want to know if I should hook this plug up or not?

 

You can leave that unplugged. A lot of people remove 'em or just leave it there.

You still throwing codes?

 

well 21 is finally gone is was something really stupid I'll have to tell you about it later. the only plug that isn't plugged in is the one I listed, I still have to fix 5 and 7 though which are cake to fix, my TPS isn't installed yet and I don't have all the vacuum lines hooked up either