What's wrong with my S13??

[Nitrus0nous]

About a week ago I posted about my car sputtering between 3 and 4k rpms, and having a very poor idle. All of a sudden when i went out last night, the sputtering stopped. It did it on my way home fromn work, but when i went back out maybe....2 hours later, it wasnt doing it. So i figure, this is great. Even though i dont know what the prob was in the first place, its nice that it no longer does it. BUT, now that that problem is gone, my idle has gone to ****. Now when i'm stopped somewhere, rpms fluctuate more than ever, anywhere between 600-100, it didnt stall out, but it did go very low. Also, when stopped, im smokin from my exhaust. this occurs about...75% of the time, other times it seems fine. I dont know what the deal is. Any help? please

thanks

[NeverEnuff]

kindof sounds like a leeky injector or vacum leek

[Nismo_Freak]

Black or Brown Smoke = fuel pressure or fuel injector issue White/Blue Smoke = either headgasket, blown rings, or fubared valve

Does the car have a miss?

Have you checked your coolant for traces of oil?