My idle is jumping up and down at idle.

It didnt used to, of course it didn't, otherwise I wouldn't be asking

When the car is fully warmed up, or while say..... I'm at a stoplight or something, my idle revs drop to way low like 200rpm, then shoots up to 1500rpm, then it drops back down to 200rpm, then back up to 1500rpm, repeat. Car almost feels like it's about to stall out at times. Just when I think it's going to stall, the rpms jump back up.

It's been like this for a few weeks now.

My setup is custom turbo setup, T3/T4, Tial WG, Greddy Profec B Boost controller, Hondata 2B.

Does this have something to do with my turbo setup? Or something to do with some other part in my car?

Any info would be greatly appreciated.

 

IACV?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by egturbo &raquo;</TD></TR><TR><TD CLASS="quote">IACV?</TD></TR></TABLE>

It could be but mine does the same thing and I changed my IAC and it still does it. If you want to fix it for now just unplug the iacv. Cold start is a lil tough and u wil have a cel but it fixes the problem for now until i can find out why mine does it.

 

mine was doing something similar to that and it turned out it was the throttle cable needing adjustments.

you could also have a vacum leak somewhere.

 

IACV? ... I ... can't.... remember... &gt;.&lt;

God I feel like such a dolt, I haven't been at honda-tech in 3 months, after I stored my car for the winter, I haven't so much as paid any attention to cars or mod stuff for a while. I can't even remeber what the terms mean.

For a while, I even forget my civic was turbo'd.

Guess I was busy playing videogames.

Stupid FFXI online &gt;.&lt;

 

Idle air control valve, its located on the back of your intake manifold and has 2 coolant lines attached to it. Unplug and see what happens.

 

My bet is on the Fast Idle Thermo Valve... Buddy just had the same problem. Located under throttle body - has coolant lines running through it.

 

Yeah I was thinking that could be it also but mine does not come with a fast idle valve.

 

take your fast idle valve off, shake it, if you hear clicking or knocking, it's a good indication that it is bad.

The fast idle valve works on teflon based rollers, that's what happen when they are stuck due to excessive carbon build up. Somebody told this a while back to me.

stan

 

dont want to jack thread nut i almost have the same setup and it does the same thing. your saying unplug the iacv and it will clear up?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vtekthis &raquo;</TD></TR><TR><TD CLASS="quote">dont want to jack thread nut i almost have the same setup and it does the same thing. your saying unplug the iacv and it will clear up?</TD></TR></TABLE>

if you unplug the IAC valve, it'll idle at higher rpm around 2500-3000 RPM.

You need to figure out where the problem seat, some good possibilities,

Vaccum leak (what does your boost gauge says ?)
Bad IACV
bad Fast idle valve (obd1)
long shot, your ignitor ground may be loose, therefore it's sputtering..(long shot)

stan

 

alright, the car has an 00 b16 converted to obd 1, does the high speed thing still apply? the boost gauge reads about, id say aliitle past .5 bar in vac, now i heard it should pull way higher than that?

 

My vac gauge read around 15 when it warms up, but I checked everywhere I can think of for a leak and can't find one.

 

What injectors are you using?

 

It can be air in the cooling system.. if it´s air in it it will effect the coold start valve and some other things so try to vent the cooling system through the vent plug.

 

I have the same problem here....but i dont have the fast idle valve anymore dint fit on the jrsc manifold (And i gues its not gone work becaus there is no place to put it).
i have a b16a1 (on a EDM crx) that is upgraded with a integra jrsc, ever since i put the jrsc on i had the problem.
doesnt make a difference if the motor is hot or cool same problem al the way.
my vacuum is about -0.8 at 1800 rpm and when it goes down -0.6 at 800 rpm.
please help me can't get it fixed
by the way the rest is all stock

greets mike ( a disapointed boost driver ).

 

check ur ground wires

 

heum ...dont know witch you mean, from motor or dynamo or what???????

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dutchmikkel &raquo;</TD></TR><TR><TD CLASS="quote">I have the same problem here....but i dont have the fast idle valve anymore dint fit on the jrsc manifold (And i gues its not gone work becaus there is no place to put it).
i have a b16a1 (on a EDM crx) that is upgraded with a integra jrsc, ever since i put the jrsc on i had the problem.
doesnt make a difference if the motor is hot or cool same problem al the way.
my vacuum is about -0.8 at 1800 rpm and when it goes down -0.6 at 800 rpm.
please help me can't get it fixed
by the way the rest is all stock

greets mike ( a disapointed boost driver ).</TD></TR></TABLE>

The fast idle valve is actually on the trottle body, the one your talking about is the idle air control valve and it bolts up to the manifold.

 

my friends car started doing the same thing when he got hondata.

 

nope ... with the b16a2 it is but not on the b16a1 (europe version) there it is at the manifold under the throttlebody (but attached on the manifold).
the eacv is indeed siteways on the manifold.

greets mike

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Cruiser G &raquo;</TD></TR><TR><TD CLASS="quote">my friends car started doing the same thing when he got hondata.</TD></TR></TABLE>

same here.
I'm also running an old staged system (4b) and a P28.
I'm hoping the P30 will fix it, but I'm not sure anymore.

FYI, I spent nearly 3 hours tuning the idle, and it doesn't fluctuate as much anymore, but now it hovers around 1000-1050 rpm.

to frustration.

 

this just started to happen to me as well, except i have an auto.. and rpms go from 800-1500. (only does it when in "P or N" and after a drive.) does not occur when the engine is cold. i was gonna try cleaning the iacv and throttle body.

 

okay, I will check my IACV and my Fast Idle valve as well.

Thanks for the info.

 

Here is my story for ya, when my integra was turbocharged 1 year ago, the idle surge became a problem after i had the head off of my car 1 time. Anyways I just got done converting my integra back to NA and got it started up tonight with the same ******* problem a real bad surge from 1000-2700rpm.

The thing that really ticks me off is that I have a different head on there, a different manifold, a different IACV, and the fast idle valve isn't even hooked up and I'm still getting this anoying surge.

As of right now I can only think that this has to be a vacum leak, so tomorrow i'm gona hook my boost gauge back up and go crazy with soapy water.

I will post back up with the results tomorrow night, if I have any that is