Idle Problem Is Over The Top! Help!!!

I need help from someone who has experienced the problem that I'm having. My '89 Nissan Pulsar is idling at top speed when I'm at a stop light (with my brakes on), when I put the car in nuetral too. And it's actually going down the road without me even touching the gas pedal. I'm truly at a loss. Has anyone ever heard of an idle censor chip? Has anyone every had this problem? I don't want to go into a mechanic and get taken on this. I'm into this car for way too much already. Please help? :lol2:

My '87 pulsar has the idle adjustment on the side of the ecu (mounted under the passenger seat)....turning it fully clockwise engages a diagnostic mode. Someone may have done this and forgot to turn it back down to its regular setting. Don't know if your '87 is the same, but I thought I'd say what I know just so its out there.

might also be a defective idle control solenoid.....just another thought.

I would check your hardware first. It is most likely your dash pot. This is on the right hand side of your Throttle Body (carberator). It looks like a small piston with a rubber boot on it. Sometimes the rubber will get old and crack allowing crap to get in there and prevent it from moving. It's main purpose is to slow your deceleration. You may want to just spray it with WD-40, or just go replace it if that is the case. This is easy to determine if you just press on it, and it moves easily or not. The next thing would be your ECM diagnostics. Go get a Chilton to figure out the codes. But, I bet you it is just a sticky Dash Pot.

Oh yea, forgot to mention. If you don't know how to check your ECM, or if the trouble shoot above does not work out for you, there is an idle speed control module located on the left hand side of your Throttle Body (Carberator). It is a long cylinder shape that sticks out with a white connector attached to it. You may want to get a Chilton, and see how to test this with a Multimeter to see if it is working properly. I think you can just unplug it, and if your car turns off, then it works, if your car still idles, then it is shot. Hope this helps.