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Old 08-23-2016, 07:33 PM   #1
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Default Cannot figure out why my idle is so high??

'92 with a '96 swap in it.

If the car is completely cold and i start it, it will idle around 1100 rpms or so albeit rich ~12.5 afr.

As soon as i touch the gas, rpms jump and will hover around 1700-1800 rpms. With the car fully warmed up, and if I unplug the IACV plug, nothing changes???? I was going to follow the how-to related to using the breather screw to set idle without IACV involvement, then run the tests to establish open/closed values for closed loop idle, but apparently I can't even get that far into it...

My breather screw is all the way in and my throttle body plate adjustment screw is barely touching the throttle mechanism (but not putting pressure on it as to holding it open at all). My throttle cable also has a bit of slack so it's not holding it open from what I can tell.

Attached is my current MSQ file and a few idle logs on that MSQ file. I've been reaching out to Brain but I figured i'd post up here too. The car is constantly hitting over run fuel cut so it has an up-and-down idle.

Car is running sequential injection, braineack built MS2, garrett gt2560r, and has a walbro 190 and fuel injector clinic 650's.

I've verified that both nipples on the back of the intake manifold (runner 4) are capped still.

Looking at the spec sheet for these injectors, it shows the offset value should be 1.20ms @ 12v and .93ms @14v at 43.5psi of fuel pressure if that helps.

Help/suggestions/ideas appreciated!
Attached Files
File Type: msq BraineackAdjustments8_23.msq (109.8 KB, 24 views)
File Type: msl 2016-08-23_18.30.10.msl (351.3 KB, 26 views)
File Type: msl 2016-08-23_18.35.20.msl (179.5 KB, 27 views)
OGWar is offline   Reply With Quote
Old 08-23-2016, 08:00 PM   #2
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Are you using a 1.6 or 1.8 throttle body and IAC? Have you run the idle test to see if the valve is functional at any duty cycle? It looks like your minimum duty cycle is like 6, which is very low. I'm not sure if 1.8 NA IAC's act the same as 1.6's, but if the 1.6's are set at too low of a duty cycle, they are unresponsive and idle high. Try either running the idle valve test to see what your true operating range is and set that in the closed loop idle settings.
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Old 08-23-2016, 08:05 PM   #3
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Quote:
Originally Posted by acedeuce802 View Post
Are you using a 1.6 or 1.8 throttle body and IAC? Have you run the idle test to see if the valve is functional at any duty cycle? It looks like your minimum duty cycle is like 6, which is very low. I'm not sure if 1.8 NA IAC's act the same as 1.6's, but if the 1.6's are set at too low of a duty cycle, they are unresponsive and idle high. Try either running the idle valve test to see what your true operating range is and set that in the closed loop idle settings.
Sorry forgot to list that.

I'm using the ENTIRE setup on the 1.8 motor. I spliced 1.8 pigtails onto my stock 1.6 harness for the iacv plugs and vtps plugs.

So yeah, I'm using vtps too.

Have a link for a good how-to on the idle valve test?
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Old 08-24-2016, 08:35 PM   #4
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Is the idle valve test conducted after the car is fully warm? I would link to the documentation I found about this but its from another forum.....is that frowned upon to post the link here so you can see what I'm referencing?
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