How do you adjust the idle?

Daryl

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I idle at 1000rpm. Maybe I’m just used to my truck and wife’s SUV (800rpm idle), but it just bugs me. I’d like to adjust it down to 800rpm. Is this possible? Is it as simple as adjusting a carbureted engines idle? Will I have to make adjustments elsewhere so the computers talk nicely to each other??

Thanks for any/all help!
 

lwarrior1016

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Some of this is accomplished in the tune.

If you unplug the idle valve while it’s running, up to temp, a/c off, what happens?
 
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Daryl

Daryl

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Some of this is accomplished in the tune.

If you unplug the idle valve while it’s running, up to temp, a/c off, what happens?
Haven’t tried that (or anything else) yet since I don’t know what the heck I’m doing! Never tried to adjust the idle on this car before. We adjusted the timing by rotating the distributor, but that’s about it as far as anything related to idle, etc.

Out of curiosity, what should I expect to happen when I unplug the idle valve once up to temp with A/C off?
 

lwarrior1016

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Haven’t tried that (or anything else) yet since I don’t know what the heck I’m doing! Never tried to adjust the idle on this car before. We adjusted the timing by rotating the distributor, but that’s about it as far as anything related to idle, etc.

Out of curiosity, what should I expect to happen when I unplug the idle valve once up to temp with A/C off?
So a couple things could happen, either the car will die, or the idle will drop, or nothing will change.
 

joemomma

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BREW2L's video is a good one. Things are a little different on the 94/95. I pulled an article from somewhere but it mentions adjusting the throttle stop screw. Most people will tell you not to dick with the throttle stop screw. I got mine sorted out with via the air adjustment screw under the rubber plug on the TB. I'm actually idling around 1000 as well, I need to go back through and adjust it down some. It just sounds better with a slower idle. Let me know if you want the article I pulled, I can send it to you.
 

lwarrior1016

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Don’t forget though, guys, he just had the engine built and tuned. They might just have to adjust the idle control valve settings.

If the car still idles with the valve unplugged and then jumps up higher when it’s plugged in, then it’s an idle valve setting not a throttle body adjustment that needs changed.
 

RAU03MACH

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BREW2L's video is a good one. Things are a little different on the 94/95. I pulled an article from somewhere but it mentions adjusting the throttle stop screw. Most people will tell you not to dick with the throttle stop screw. I got mine sorted out with via the air adjustment screw under the rubber plug on the TB. I'm actually idling around 1000 as well, I need to go back through and adjust it down some. It just sounds better with a slower idle. Let me know if you want the article I pulled, I can send it to you.
Thats a bit high
Mine was at 940
Once I started to adjust the throttle body and the air adjustment screw
I got it down to 760 ish
And like I say I have mods on mine
Only problem it hates regular fuel
I have to put the octane boost in it or get super unleaded
 

tinnocker

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Good luck with the idle set. I have been struggling with this on my 94 for a couple months. I thought I had it down to around 850-900 but it has jumped up again. There are quite a few ways to do this when you Google, most are all the same with different sequence of steps. Our computer is different than the Fox Mustangs so watch out for the methods and on what models. Good luck and please post what you did if you are able to get the RPMs down.
 

07GtS197

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Yeah, but I think it’s pretty mild to meet California emissions
True but where I was going with that is that maybe the tuner set it high so idle quality didn’t suffer. Op have you tried contacting the tuner to see where he set the idle rpm’s?
 

ttocs

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I am not sure why he sent it out the door so high myself. IF he has it set at 1000 adjusting the throttle stop will not give good results.
 

joemomma

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The 266 is a good cam, has a pretty good lope from the videos I've seen. Forgot it was built/tuned - first step should be to check with your tuner and see where he set it.
 
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Daryl

Daryl

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Was able, with guidance from a member here, to bring the idle down about 500rpm. And I’m actually quite content at 950 versus the 800 I believed I was after because it idles and sounds “where I want it” and the driveability wasn’t affected at all.

So, I’m gonna stop there and not mess with it any further. Thank you to everyone who replied. Rest assured all options were considered. Sometimes the easiest solution renders desired results!

Cheers!
 
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Daryl

Daryl

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Not much, really:
1. Backed the set screw out a bit; and
2. Repositioned the throttle flange

And that was it!
 
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I idle at 1000rpm. Maybe I’m just used to my truck and wife’s SUV (800rpm idle), but it just bugs me. I’d like to adjust it down to 800rpm. Is this possible? Is it as simple as adjusting a carbureted engines idle? Will I have to make adjustments elsewhere so the computers talk nicely to each other??

Thanks for any/all help!
 

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