Did a good 2 hour street tune this weekend(sunday) on the car. Everythings perfect so to speak but the idle.. Will surge from around 600 ~ 1100rpms..

I did the usually things, there's really no vac lines on the motor, i check the vac line from the FPR to the back of the manifold, its good..
I checked around the manifold bolts, and Throttle body, i also sprayed chemtool b12 all around seeing if the car would die out, nothing..
I checked all the pluged up holes and what not.. nothing..
Was wondering what your idles could be, is it a tune problem, the idle sits good at 14.0's but was maybe wondering if there's a tuning trick to stop this.. i'm pretty stuck at this point help?

 

Try decreasing the IAC Compensation seems to work for me every time. You can also try playing with the idle screw on the throttle body.

 

idle screw is all the way in, i dont have a fast idle thermal valve neither..
IAC ?? you mean in crome?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IntegraType-R &raquo;</TD></TR><TR><TD CLASS="quote">
IAC ?? you mean in crome?</TD></TR></TABLE>


yes

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IntegraType-R &raquo;</TD></TR><TR><TD CLASS="quote">idle screw is all the way in, i dont have a fast idle thermal valve neither..
IAC ?? you mean in crome?</TD></TR></TABLE>

First, be 100% certain there are no vacuum leaks.

Second, if your idle screw is all the way in and the engine is surging between 600 and 1100 rpm's I'm guessing that opening the idle screw a little should help steady the idle somewhere in between. Try warming up the car completely and slowly opening the screw until you reach about 850-900rpm. If you have a good timing light hook it up and use it to read the rpm's while your turning the screw with the engine running. If it steadies, take a test drive to see if the surging persists. I am thinking that with the idle screw all the way in, your idle rpm is set too low, so just before the engine stalls it jumps up. I like to have my idle set around 900rpm to help keep it from stalling when I let off the gas quickly. Because I'm using a 7.5lb flywheel and modded/lightened GSR pulley it used to stall (very annoying) when I approached red lights and stop signs. Anyway, let me know if that helps to solve your problem.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Natural Aspirations &raquo;</TD></TR><TR><TD CLASS="quote">Try decreasing the IAC Compensation seems to work for me every time. You can also try playing with the idle screw on the throttle body.</TD></TR></TABLE>

I haven't used CROME for a while now, but I was under the impression the IACV control wasn't fully functional. Maybe it's been fixed since I used it, though.

OP, your car seems to be acting the same way mine did when I installed the Pro2+'s on my old manifold setup. Eventually, I learned that by propping the throttle body open a hair (as "LSvtecMike" explained), I was able to steady things out to a smooth 950-1,000 RPM idle.

Good luck. Idle sometimes can be harder to tune that everything else.

- Derek

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by D-Rob &raquo;</TD></TR><TR><TD CLASS="quote">I haven't used CROME for a while now, but I was under the impression the IACV control wasn't fully functional. Maybe it's been fixed since I used it, though.</TD></TR></TABLE>

Yes, it's fixed. It works flawlessly since 1.4.5. I could get my Pro1's idle almost like stock at 900 RPM just by playing with the slider. That is without touching the TB idle screw.

 

Well, here's the thing.. i only have 1 vac line, from the back of the manifold, to the FPR.. Everything else is plugged up with the plugs and there's teflone all around the screws, there in as much as i can, i almost **** a horse screwing these things in tight, if i go anymore i'm afraid i'll crack the manifold.. thats how tight they are.. nothings stripped.. i've sprayed the entire intake system down with chemtool, around the manifold, injectors, TB, IAC, all the lines around the head.. the motor doesn't surge or even attempt to die down. I disabled the IAC in crome and it made it a TAD better... it still surges a small amount.. but i'm now 100% sure i found the problem..

Seems that even on DC2's you need to move the fuel filter over..even with new mounts and a stiffy.. the amount of force the motor puts out is retarded on lsd.. the motor slammed back and then up again and completely took off the tps from my power tb lol..so I "THINK" its because
1) the tps is half gone.
2) the tps was never caliebrated before being put on..

I'm sure its in the tune, like i said, the tune was quick and steady so i could drive and beat on it some, it wasn't done with the datalog , it was done old school way with crome regular.. but i shouldn't have any problems.. picking up a new TPS today. thx anyway guys &lt;3 you all so much ^^

Car's pretty quick to say the least.. its pretty exciting to spin both tires.. 1/2 is actually non existence, as long as i'm about 5k, i can just punch it and they both break loose.. the manifold seems to be a better setup then the itbs were on my car.. and now that everything else is pretty much good to go..hopefully i can start driving it again..
All this w/o my hytech header on..i can only imagine what the car's doing to do when i put this on.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Natural Aspirations &raquo;</TD></TR><TR><TD CLASS="quote">Try decreasing the IAC Compensation seems to work for me every time. You can also try playing with the idle screw on the throttle body.</TD></TR></TABLE>

Is that the same as the IAC duty cycle setting in SManager?

sorry IntegraTypeR, not trying to threadjack.

 

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

Is that the same as the IAC duty cycle setting in SManager?

sorry IntegraTypeR, not trying to threadjack. </TD></TR></TABLE>
Pfft i dont put sand in my vagina, i could careless as long as everyone is understanding and learning...its all gravy.

 

your tps could deffenatly be the problem. when i first put my motor in i only put one bolt to hold the tps in just to crank it and let it warm up so i could drain the oil[it was a fresh motor]. my idle would do that also. go to looking around while it was idleing and pushed on the tps it smoothed out,even though it was setting flush before. put another screw in and bam all good

 

I AM all most 100% that is it the TPS had the same prop with the last motor i had and i change TB and it went away.... try that if u have a spare TB