rpm's dive to nearly dieng at every stop light. help!

[nwdrfter]

ok, i did search and didn't come up with anything, so, here goes...everytime i stop at a light my engine dives down to like 4 or 5 hundred rpm's and feels like it's gonna stall. i let it kinda do whatever it's doing and i noticed that it'll dive then come up to about normal idle then back down then back to normal. also i've noticed that when i brake the rpm's dive a little. or even when turning on the vent or heater. is this an alternator problem? O2 sensor. tps? maf? i really don't know. i'm still trying to figure this motor out after getting it out of a cheesy shop that didn't do as well as expected. also, at what rpm's should a ka24de be idling at? i think it;s timed at the third mark below the orange mark right now.

motor stats: 93 ka24de, currently in an 89 s13 coupe, repalced all ignition already. tried to time it as best as i could. ND WELL, That's about it so far.

thanks anyone!

[240crawler]

Since you put it into another car, did you keep any of the emmission controls? I only ask because when I pulled off my charcoal canister, I had funny idle issues like that. I could only idle with the A/C on, because the computer raises the rpm at idle for the compressor. If I ran the car semi-hard, then went to stop, rpm would jump around then die. Try some fuel cleaner, also. I recommend Berrryman's B-12. There is none better in my opinion. Do not spill it on paint, or let it stay on your skin for very long. You can find it at Autozone or Wal-Mart. Cost is around $2.50.

[nwdrfter]

thanks, i'll try that. as far as i know they put all the emissions stuff on there. but i really have no idea what the heck i'm talking about to be honest. i think all the egr stuff is there. or so i've been told because someone said to take it all off for better performance. i'll try the berryman's b-12 and see what happens. it's really wierd, it only does it now when it feels like it i guess. i messed with the idle adjuster thing and it idles at about 950 now and only half the time does it try to stall out at a light. anyways, i'll let ya know what happens with the injector cleaner. any other ideas would be great too. thanks again.

[nwdrfter]

oh yeah, what's the charcoal canister? looks like? where?

[darko240sx]

Spark or low idle volts will do that too

[KADreams]

Coolant temperature sensor and/or it's harness connector.

[nwdrfter]

what about if it acts like it's jumping when reving? like cutting out and then jumping up in rpm's as i throttle. like it's missing then firing properly? approx. in the 2200 to 3200 rpm range.