sr20det slight idle problem

[nicks240sxs13]

hey guys i was wondering if someone could help me figure out my idling problem on my sr20.
a couple of days ago my sr20 was idling at 1200 rpm, i boost leak tested it and fixed all the leaks, now after i come to a light or rev it at all the rpm's drop down to about 600, vaccumm at about 12, and sounds like its cammed. it only does that for about 5-8 seconds then, by its self, will rev up to 800 rpm and vaccumm at 18. and it will say perfectly steady at 800 until i rev it again or drive and stop. It almost seems as if its not getting enough of somthing for those few seconds, or maybe it just needs a tune?
all i got on the motor now is
walbro fuel pump
isis pullies
isis bottem mount manifold
greddy ti-c
fmic with ssqv
s15 turbo @ stock boost
circut sport lines
cold air intake.

i've had the sr20 for about a year now and the s15 turbo on since november and its ran perfectly fine.

So do any of you know wat might be causing this weird idling problem?

[BiG MiKE86]

Clean the IACV? Could be getting stuck

[nicks240sxs13]

just take the idle bolt thing out and spray carb cleaner in it?

[nicks240sxs13]

seriously.. i sprayed carb cleaner in the IACV and tightened up the lines on my catch can. and its running worse, it wont even go up to the 800 rpm anymore. i start the car when its cold and it will idle great, but once i touch the gas at all thats when it starts to idle like shit.

originally it idled perfect, one day it started to idle at 1100 - 1200. i fixed a boost leak i found, and now it wont idle for shit!. i have no idea what to do anymore guys. this is my DD and i need some help guys.

anyone got any ideas?? thanks!

[jr_ss]

You can start by adjusting the IACV. Warm the car up and then adjust the screw in/out to increase/decrease idle rpm. I have a feeling you just tightened that screw all the way in and didn't adjust it properly.

[nicks240sxs13]

ha nope. i've never messed with that bolt.. or atleast until a day or so ago.
yea while it is warming up it really doesnt like to idle to much, after its warmed up and I come to a stop the rpm's drop to about 600-650rpm and 12 vaccuum. then after serveral seconds it does go back to 17 or so vaccuum and 800 rpm.
i just unscrewed the idle bolt(i counted 17 half turns, so i put it right back where it was) and spray some carb cleaner in it, not too much, and ran another boost leak and sprayed soapy water all over my piping and intake manifold/IACV area and found nothin.
But when the car is running i tryed pinching the hose coming off my cold pipe going to my IACV and the idle does change, so i guess that means the IACV is sort of working?

Should i just mess with and adjust the IACV a bit, check for vaccuum leaks, or what? i really do not know was eles to do anymore lol.

oh and its an s13 red top sr20det with a s13 blk top ecu in it, its been that way for about a year now lol, maybe i should swap back to the red top ecu???

[a7olyte]

The IACV can only allow so much air in. You may have to open the throttle body just a tiny bit and then adjust with the IACV.

[JDMRIDDAZ]

check if iacv is getting 12v getting
i rewired all the power switch wires to ecu with a relay..
it worked perfect..
s13 are old cars and tend to have floating issue w voltage in the harnesses..
at least mine did and others i have worked on

[JuMPiiN]

You should adjust the idle screw I had the same issue, adjusted the screw and it idles fine at 1100. not sure on your vac being at 12 though ? mine stays constant at a 20.