my RPM's drop to 200 rpm when foot off throttle.....more---->

[yospeed]

I could use some suggestions as to what is causing my car to drop RPM's all the way down to anywhere from 50 - 250 RPM's after I depress the clutch while the car is in gear and moving. This also happens in neutral when I rev. In both cases, the RPM drops really low and then bounces back up after the car makes a complete stop. However, at times my car will die out because of the low RPM's. The car will start back up each and every time.

So right now I'm just looking for any suggestions on what to check out. I'm thinking dirty air filter or MAF sensor. Any other guesses?

[p00t]

happens to me also, but will only dip down to 500-600 at the lowest since I removed my AIV.

3 things to do:

1. Clean/Remove AIV (PAIR) system (theres a sticky in 240sx Technical about it)

causes some exhaust gas to seep into the intake which will cause car idle to dip more than usual. It isnt the sole cause of the problem, but it makes it worse. Some people have amazing results afterwards, some it doesnt help at all.

2. Clean the Idle Controll Valve

when the plunger gets gunked up it will not adjust properly and the idle will bop up and down and act quite erratically. also check its ground, if the ground wire is corroded the plunger cannot function properly. it is located under the intake plenium on the rear side of the engine. If I clean it soon I will post a walkthrough but no promises.

3. Check for intake leaks.

these will cause more air to seep past your MAS than it thinks is supposed to be flowing through into the engine, so it cannot adjust the Air:Fuel ratio properly.