1993 240SX : VERY rough idle at cold start. very sad..

[SPEEDingMoNK-S13]

hey guys, its been along time.. if any mods are reading this post can i get my old tag back 'SPEEDingMoNK' its been years and i forgot my password and done have that email any more.. anyway...

Ok heres the deal I have a '93 S13 w/ the KA in it, latly (starting on 2006/7/3) when i start the car after its been off for awhile it starts right up but runs soooo rough the whole freaking car shakes.. it realy pisses my off. if i hold the engine at 2k rpm or higher it goes back to runing nice and smoth, untill i take my foot off the gas. the idle stayes in place ~1k when cold doesnt move much but it still shakes the whole freaking car. once it warms up (coolent temp gauage goes back to norm spot in middle) it drives far better but feels a little booged down and its getting worse...

the last few things that have been done to the car are...i had the transmission rebuilt at a transmission shop about a week ago...drained alittle oil and ballanced and rotated the wheels...

right before this started i was stuck in 4th of july traffic and was idleing for probley 2 miles.. parked the car came back after the fireworks and it started shaking when i started the car. and it has done this sence

now i had codes 33 and 34 for the knock sensor and 02 sensor in the computer before all this started and they are still there. (yes i have cleared them). i would like to state the fact that im not a mechanic, but im a pretty smart mofo who can turn a wrench, im also a professional slacker and like long walks on the beach, and long drives on those country roads +) now im broke and would greatly perfer not to NEED to take my car to the dealer and have them do the diag and/or repair, but i also cant aford to break my car.

so whats the problem? is it simply both? the O2 sensor causing the rough as hell cold start? and the knock retarding my timming thus slowing my down providing the bogged down feeling? if so what should i do? replace the 02 sensor and try to find the issue w/ the knock sensor? also

this is my 2nd S13 and im planing on keeping it for ever, i also wanna 300ZX, 350Z and a G35 for my girl but that is mainly as pipe dream

thanks for any and all help - peaceNISSAN > *

[180fan]

I'd wiggle the plugs at the injectors and see if that smooths things out a bit before replacing sensors and what not. Post back what you find

[SPEEDingMoNK-S13]

since i had the code for the o2 sensor, i checked the manual for the diag on it. it said to check for co-ta-new-ity and if you have it replace the sensor. so i just replaced the sensor. its greatly easyer getting the o2 sensor in and out w/ the right tools. you cant realy use a regular wrench since you can only turn the sensor a few degrees due to the A/C hoses and firewall on either side

O2 sensor @ nissan = $160O2 sensor @ Advanced = $40

sorry nissan if i was rich id have a 350Z...

btw that fixed my problem no more code 33 and no more shaking, it feels healther also. peace