Quinn,The brass screw is an air by-pass screw and is the only way to adjust the idle. You can loosen the clamps on the throttle body and rotate to access, and adjust with engine running, but easy enough to leave it in place and use a long or angled screwdriver. Clockwise to decrease idle speed - one quarter turn will reduce by about 200rpm. "Do NOT adjust the throttle stop screw on the side of the throttle body unless you are using the factory software to calibrate the base throttle opening."This from the workshop manual.Electronics & injectors is all just magic to me.....
Where is the idle adjustment screw? I need to lower the idle. Thanks.
Prof:I had made a short video several months back on idle adjustment - it is on youtube. Never mind the title (which says TPS on it, but as Will has written it is only an air by-pass screw).The brass screw can be rotated with a LONG flat screw driver - without the need of an angled screw driver. Keeping the idle on the high side has some benefits. Do you have a tachometer ? http://www.youtube.com/watch?v=w51XKoubABI
Oh yeah, that is perfect! THANK YOU!! Where can I get a portable tachometer? What does it plug into (besides being grounded on the fins)? It's time to spend more $ on the C5.