ook guys i'm posting this for a friend since he seems a bit lazy to put it up for help...

did a LS swap into a EK hatch...believe the car is a 2000 obdii and the motor we got was a 99 LS....we got everything in....mounted up, did timing belt, shift linkage all those stuff. so we fire the car up and let it idle...idles good let it warm up and then we adjusted the timing....so its good. so i give it a some quick revs...it revs up fine...sounds really good, no knock, ping, or detontation.....but as soon as the revs come back down..it won't go back to idle...it just dies.. now...the car only dies when i rev it real quick like when i give it a quick step on the throttle....but if i gas it slowly and then let go slowly..the idle would come down struggle a little and then stay on...but with a quick rev..it struggles and then shuts off....

i'm thinking it has to do with fuel....injectors possibly? or could it also be a bad ECU? need help so suggestions guys

 

are all your vacum lines properly connected? exactly same thing happened to my friend's car and it was a simple vacum line.

 

CHK VACUM LINES AND WHAT ECU ARE YOU RUNNING?

 

Sounds like the vacuum system isn't completely sealed (or hooked up wrong) or the IACV is fucked..but that would 'cause irradic idle so I doubt it's that...pressure check the vacuum system, I read htere was a way how...I never really looked into it though

 

so uthink its vacum lines huh? i don't think it could IACV because..if it was the car would have a fucked up idle...it only dies after a quick rev...i sprayed all the hoses down with some throttle cleaner to see any idle changes but nothing...but i'll look over all the hoses again

BTW i think he is running a conversion harness with a LS ECU or something...i'll get more info ont hat

 

ok still having problems....only vacumn leak i see is on the intake mani there is a small vacumn nipple that isn't hooked up...friend said its only on auto intake mani? not sure what its for but if plug that vacumn source up car runs like ****...u can rev it and it'll idle extremely low or die out...but if u leave it unplugged car would not die.

seems like now the car doesn't wanna die out anymore but the idle just keeps surging and goes up and down after revving it....idles at about 1300....i cehcked timing and everything...tried messing with the adjusting screw nothing....

only thing i can think of is maybe MAP sensor? or d-series, b series and OBDI or OBDII make a difference in MAP sensor? i would think so....at this point i don't kno anymore..

 

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