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Old 05-26-2010, 12:13 AM   #41
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Bah, TS doesn't have those gauges setup by default. JS4 is normally used for EGT, but I'm not sure the output of the EGT gauge would help any since it's calculated. Well, give it a shot and see what egtGauge is doing.

Edit: What are your low and high speed idle setpoints?
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Old 05-26-2010, 12:33 AM   #42
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The other thing that could be a problem is that JS4 is too low to start with. The way the code works, is if JS4 < 2.5v, then it switches to the fast idle speed. But if you don't have anything normally keeping JS4 > 2.5v, then it might trigger the fast idle speed all the time. So try increasing your fast idle speed to see if your idle follows it.
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Old 05-26-2010, 12:39 AM   #43
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My fast idle is 1300 and low is 900. I'll give it a try tomorrow. It's already late.

Actually, now that I think about it. Changing the fast idle speed setting did have an effect even though the car was already fully warm. Think it might've been active the whole time? If I'm to understand this correctly, if JS4 is grounded it's supposed to turn the fast idle on? Or is it the other way around?
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Old 05-26-2010, 01:06 AM   #44
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If the fast idle speed was causing an effect, even though the car was warm, then JS4 is just sitting too low.

You can't just ground JS4. You need something to hold the input high when it is not grounded. Normally the A/C or Heater input would do this.
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Old 05-26-2010, 01:27 AM   #45
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Actually now that I think about it more, it had to be working. Just all the time. Reason being, is that the idle was very high when I had it in closed-loop mode, but I thought that was due to the wonky settings from the last time I tried to use it (haven't used it since). So to do this properly I need to make sure it sees 5v when the a/c is off, but the factory circuit shows 12v. Could it be as simple as using a resistor?

Even better question, can you change the code so that it works in warm-up mode only?
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Old 05-26-2010, 02:17 AM   #46
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Yeah, you need to bring that 12-14v down to less than 5v, but greater than 2.5v. You can use a voltage divider, or a 5v zener diode. Here's a simple circuit using a voltage divider and two commonly available resistors.

Try the code in warmup mode. It might work. I don't recall. If it doesn't work in warmup mode then I'll take a look at the code.
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Purge Valve Solenoid-screen-shot-2010-05-26-1.19.43-am.png  
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Old 05-26-2010, 07:08 AM   #47
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I'm going to assume it doesn't work in warmup mode because the idle drops to normal when I switch to it. Also in warmup mode the idle is set for a specific DC rather than a target RPM. I'd have to imagine that'd be the major difference.
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Old 05-26-2010, 11:42 PM   #48
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Ok I hooked it up properly using a voltage divider like you showed and I can say it definitely works. My only problem is that it responds kinda slowly. Like normal idle with the a/c off is 9%. The car is happy with the a/c on at 13%. The problem is that when I turn the ac on it takes a good 3 seconds or more for it to slowly ramp up to 13%, the whole time it's struggling (or stalling).

Truthfully I still think that it being able to work in warmup mode would be better, as closed-loop mode SUCKS and is pretty much un-needed (I've never had any idling problems due to a/c, headlights, power steering, heated seats, etc.. only a/c). If it could instantaneously switch to an arbitrary DC it would work way better.
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Old 05-27-2010, 12:02 AM   #49
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Let me see your idle settings. Maybe we can improve it's response. I don't recall having that problem.
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Old 06-01-2010, 07:59 PM   #50
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loaded the code today waiting on my resistors to come so i can wire it all up and give it a go i will keep you posted
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Old 06-01-2010, 08:01 PM   #51
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Great, keep us updated!
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Old 06-01-2010, 08:09 PM   #52
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justin did you check to see if it works with warmup only mode as well? or do you have to edit the code?
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Old 06-01-2010, 08:28 PM   #53
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Just did -- it won't work in warmup since warmup doesn't have a fast idle speed. Editing the code to modify the DC is trickier, since I need to add an additional variable, and there is no memory space left. I'd have to go through and take out some other features (like NOS...) in order to do it. It would just take some time (which I don't have right now). So for the time being you'll have to use closed loop.

FYI, I have absolutely no trouble with closed loop... works fine for me.
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Old 06-01-2010, 10:43 PM   #54
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closed loop for me seems to react to slow for lights/PS and so on. if you want to take a look at my settings here is my msq. maybe you can give me an idea on what i can fix
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File Type: msq HiRes-Turbo-Jume-1-10-wclosedloop.msq (32.2 KB, 66 views)
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Old 06-01-2010, 10:47 PM   #55
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I'll take a look. What yr is your car? Oh wait... is it a miata?
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Old 06-01-2010, 11:22 PM   #56
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Its a 92 mustang w a 5.0
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Old 06-01-2010, 11:44 PM   #57
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Not sure how much I can help in regards to settings specific to your car, however at a quick glance, you will definitely want to increase the Fast Idle Speed to something higher in order for my code to be effective. I use 1300.

If you say it reacts slowly, try reducing the Fast Recovery speed to something much lower. Mine is set to 5. You might also want to set your Minimum DC to something slightly higher than the Closed DC.
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Old 06-02-2010, 08:39 AM   #58
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Quote:
Originally Posted by JustinHoMi View Post
Not sure how much I can help in regards to settings specific to your car, however at a quick glance, you will definitely want to increase the Fast Idle Speed to something higher in order for my code to be effective. I use 1300.

If you say it reacts slowly, try reducing the Fast Recovery speed to something much lower. Mine is set to 5. You might also want to set your Minimum DC to something slightly higher than the Closed DC.
i will give that a shot.My min DC is 9 because any higher it wants to idle at 1000 instead of 900 so i think that might be ok, anyway what Freq are you using i am using 33 as of right now. just wondered if changing that would help out at all as well?
i will keep you posted once i start testing
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Old 06-02-2010, 12:02 PM   #59
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The frequency entirely depends on your idle valve. It's important, because an incorrect freq can damage the valve. A buzzing valve is an indication of an incorrect frequency. If other people with mustangs are using 33, then that is probably correct. If you can reconnect your OEM ecu, and have a multimeter that can measure frequency, then you can check it yourself.

The equation is 10000/x = real frequency

In your case, it's 10000/33 = 303

So, at the moment the MS is running your idle valve at about 300hz.
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Old 06-02-2010, 03:21 PM   #60
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300hz is the right freq that ford uses. thanks man i will keep you posted when i get everything wired up
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