idle troubles

[ZEmadman]

having some trouble idling. when im in neutral sitting at the light, everthings fine, i idle anywhere between 900 and 1100rpm....solid. but if i shift into first and continue to hold in the clutch, it revs to 2k then drops, then revs then drops over and over until i engage the clutch and go, OR go back into neutral.

it's not really affecting the performance of the car im just curious if there's a way to possibly fix it.

thanks

[mdavis]

I don't know why putting it in neutral would make a difference.. But it sounds like you need to recalibrate your TPS... I has having some issues like you, I pulled over in parking lot and rotated my TPS until it stopped... I also had some other less bizzar idle issues more recently that were fixed by recaliberating. I would get the link to the instructions for ya, but I can't seem to find it... I'm sure someone else has it **hint hint*** sorry I couldn't be more help.

[IanL]

For TPS adjustment, see here.

Your idle is set a little high, which may be a factor. Adjust it down to 640-700, with the air adjusting screw, with the engine warm and all auxiliaries off.

Another possibility is a small vacuum leak - a large one would affect performance when driving as well.

Also check the PCV Valve. Gently pinch the hose with pliers to block it, and check if the engine speed increases. If it does, the valve is probably stuck open.

If that doesn't work, you can overcome the issue by disconnecting the clutch and neutral switches. The way to do this, without affecting cruise control and the starter interlock, is to disconnect the Brown/Yellow wire to ECU terminal 1R at the ECU. But this is a last resort, because you would be just masking the problem, which could be a partially defective IAC valve.

<small>[ October 07, 2004, 02:49 AM: Message edited by: IanL ]</small>