get rid of the idle crap

[turbo90]

I got all of the turbo stuff on a few weeks ago, and the only big problem I'm having is with the idle. Sometimes it does, sometimes it doesn't. It also has a bad on/off touchy throttle at very small throttle imputs.Background:KA24E, basic homemade kit, SAAB turbo, AICV gone, EGR blocked, A/C gone, 8:1 FMU, FMIC setup, Atmo BOV (I know this may be part of the problem and I am going to recirculate it soon), Timing has not been touched, and right now the IAA unit is connected to unmetered (before the MAFS) air.I believe I have tracked down all of the vacuum leaks, and am only boosting at 3 psi for now. Should I try a new TPS?ANY ideas guys? I'll try almost anything to get it to idle and to stop snapping my neck when I feather the throttle thanks,TB

[PapaSmurf2k3]

Check your engine grounds, That sounds a lot like what was happening to me when my engine ground decided to break.

[turbo90]

yeah, the big one that goes between the battery and intake mani is tight, but i'll double check all of them. any of the KAETers out there have any imput on the location of the IAA inlet? does it need to see boost, or metered air, or do i have it right?????

[skatanic28]

i thought the iac was supposed to go to the cold pipe?

and is your bov sucking in air at idle?

[nissanfanatic]

IACV hose should be connected to the pressure side of your intake piping. If you don't, it will be destroyed. Check to see if the BOV is sitting open at idle. Check for boost leaks.

[toki]

=, AICV gone, EGR blocked, A/C gone, 8:1 FMU, FMIC setup, Atmo BOV (I know this may be part of the problem and I am going to recirculate it soon)

AICV? Do you mean IACV standing for the IDLE AIR CONTROL VALVE? I hope not.

Check all your couplers to make sure they are fitting tight and think about recircing that bov.

[hysteria]

yeah pretty much all things connected to the intake manifold ned to be on the boost side...

all air intering the engine should first go through the filter, through the mafs, and then through the turbo into the boost side, where it either goes through the throttle body or the idle air passages...if you had it hooked up incorrectly chances are the iacv is done for, and so you'll have to block it off. the problem is that it's damn near impossible to get to without having the manifold off, or at least half of the manifold off.

my iacv spring was broken and i just didn't feel like dealing with it anymore so i blocked mine off completely, and my car runs like a charm. before i did this the idle was very erratic and the car would die on occasion. try adjusting your idle screw, check to make sure you have no vacuum leaks, and make sure all of your vacuum controlled devices are hooked up right and functioning properly (bov, wastegate -if it's a tial or that style with the two nipples one on top one on side it should be hooked up on the side/bottom...), make sure as has been said before that all piping is tightly sealed adn there is NO WAY any air could get into the engine without passing through the mafs first. if air is getting into the engine without going through the mafs, the engine will do weird things.

[nissanfanatic]

I just recieved my 1.5" SS braided recirc hose from Summit today. RPMs don't drop at all now. I really recommend recirculating. Car also drives so much smoother.

[turbo90]

yeah, I'm going to recirculate the bov valve this weekend, and I'll put the idle stuff on the cold pipe and see what happens, thanks for the replies!!TB

[xxtrizz]

It appears however that your idle issue might not be cleared up as I noticed you didnt comment about it. Your engine could have had idle issues prior to turboing it, if that is the case I would just reccomend cleaning out your intake tract I ended up taking my intake mmanifold to a rebuild shop and had them drop the bare bones manifold in the hot tank, after that things that could affect idle and you would think im craxy but a little air in your coolant system can set your idle off, mine used to be low at idle and then high and low but steady when at the specified amount however the air in the tract was causing the idle not to sit at 750. Rather fluctuate high or fluctuate low. Once fixed and new radiator hoses attached the idle was steady. Regardless if you take the vehicle in for an idle3 adjustment 80 bucks of your time Nissan will tell you if any electrical part is broken or reading wrong. Then you will know for sure what to replace if necessary. If not electrical and they attained an idle of 750 but still fluctuates I would reccomend cleaning the bugger IManifold or otherwise there is something that isnt correct, fule filter etc....

[sil80drifter]

How good does the SOHC work w/out the IACV? What about that second valve that sits right next to it, they areboth connect by a big fat air hose. I am thinkingof ditchign all that stuff (EGR and carbon canister already gone), because it's just too busy and seems a bit useless. Is the idle correctabel reptty good with just the throttle screw? Will it idle at normal RPMs or hgiher RPMs? Are there winter issues (problems with cold start/idle?)?

sil80

[hysteria]

don't know about the E but my DE runs better, because the iacv was screwed up. i took it off backed out the idle screw a little and it runs like a dream. i will bet that the E will be just the same. i mean iacv isn't always on, only during warm up so if your car idles fine under normal driving conditions (when you stop at a light or once the car is warmed up) it will be fine without the iacv. the only thing is that when it's cold it takes a while for the engine to warm up... but if it warms up slower it will probably last longer. there are no negative effects to removing the iacv, but i let my car warm up to normal temp before i ever drive it, and it just takes longer now.

[sil80drifter]

is your idle high or normal? I was under the impression that there is always some valve that controls the idle, cold or not, aside from the valve that is on only during cold cinditions.

sil80

[turbo90]

ok, here is my idle: wideband reads 10.1-.3 will idle fast for 3-4 secs then die. wideband reads 19.9+ same deal. I can blip the throttle to keep it alive. I have removed the AIV (by exhuast mani), egr is blocked and bypassed, carbon canister is removed, I still have SCVs, AAC, and air regulator.Idle was fine until I went turboI would like to get rid of everything like sil80 was saying, has anyone had any success doing this? perhaps I'll just do it and let you all know how it runs. anyway, what about the part-throttle jumpiness?TB