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HondaDustR HondaDustR is offline
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Join Date: Jan 2007
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Originally Posted by Armon View Post
Oh, yeah, I followed Clark Garage instruction, when B & C terminals jumped it got about 1000 rpms. without it the car idles around 900.
But you said before it fluctuates from 600-800. If it idles around 900 without the jumper, that's about right. Please explain. Is that with the ICV blocked? Try adjusting the idle bypass screw shown in clarks garage so that it idles around 850 or so with the terminals jumped and see if that helps the ICV work properly. Have you tried unplugging the O2 sensor for the time being to see if that changes anything? Is your throttle cable adjusted correctly so that the throttle body is allowed to close completely reliably against the idle stop every time the throttle is released? Is the throttle position switch adjusted correctly so that you hear the click of the idle switch just as the throttle reaches the idle stop? Check all of the other hoses that are connected to the intake manifold for condition and tightness of the clamps. There's one directly under the "log" part of the manifold that connects to the brake booster venturi and so on. Make sure nothing is cracked. Check that your oil fill cap is tight and the rubber o-ring is still there and intact. Is it possible the fuel injector seals or the intake manifold gaskets are leaking? I had a manifold gasket blow out all of the sudden once awhile back (probably from an intake backfire) and that wrecked havoc on the idle IIRC. Any vacuum leaks will make the car run lean, which will increase the chance of intake backfire.

Originally Posted by Gawernator View Post
Very useful info! Luckily my car has been running pretty well at part and wide-open throttle, and very well with my Wilk's Chip turned on (which bypasses the O2 sensor, the Race version). Is the throttle switch the same as the throttle position switch? I have been trying to figure out if mine is on the way out or not.
They're the same thing, although for the NA engines all it is are two switches. One is the idle switch, which clicks, and the other is the wide open throttle switch. It's pretty easy to check. Just unplug and use a multimeter set on ohms. The center pin is common and each of the outer pins goes to each switch. The idle switch should read at or near 0 when the throttle is closed, and the WOT should read at or near 0 ohms at about 90-100% throttle position. I have had problems with mine in the past where the WOT switch was unreliable. Eventually had to take it apart, found that the actual switch contacts were just fine and there had to be a bad connection between the switch and the pin, dig through the plastic with a razor blade until I got to where the WOT pin connected to the internal switch connections (it was cast into the plastic base!) and soldered a jumper wire from the exposed pin to the switch, as the spot weld on the original connection had failed. It beats paying $80 for a new one.
1987 silver 924S made it to 225k mi! Sent to the big garage in the sky

Last edited by HondaDustR; 11-12-2012 at 05:53 PM..
Old 11-12-2012, 05:41 PM
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