I'm not sure, but I think it might be caused by the BOV. I'm going to go try tuning it again after I finish posting this.

But basically, after depressing clutch pedal and going ot neutral the RPM will go up to 1500, down to 800 (where it should be) up to 1500 for about a second, down to 800 and back up to 1500 for a second, then down to 800 and sit there.

This is on a D16Y7 motor, I switched intake manifolds for the D16Y8 manifold and still using a Y7 throttle body...
I've tried adjusting the idler screw, (before it was dropping all the way down to 0 rpm and killing the motor in idle). It seems to me like its a vacuum leak, but I've checked all the connections and there aren't any leaks I can hear or see.
Are there any ideas as to what else may be causing this?

 

Okay, adjusted the BOV spring. I put in about 6 washers, and although the sound of the BOV has got a stronger noise to it, but still having an idle problem.
Does anyone know if this can be caused by the GReddy brain box included with their kits?

 

Thats very possible that the greddy box is doing that, since its designed to trick the ecu into thinking the engine is cold.

Try this, next time it starts bouncing, disconnect the charge pipe, and you should see a hole (passage) on the inside of the t-body, this leads to the idle air control valve, you should be able to put your finger over it to make it stop.

Jeff

 

Hmmm okay, and if it drops down to normal idle is it the box??? or what will this determine? :) thanks jeff

 

if you put your finger over the passage and it drops down just fine, it could be the Idle air control valve ------- up (possible) or the greddy controller (very possible) I am assuming you are using the "Black Box" of lies?

Jeff

 

yes... until I can afford an SAFC