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Old 01-27-2010, 03:33 PM   #41
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Quote:
Originally Posted by Jeff_Ciesielski View Post
Mechanical idle is the way to go, you might need to adjust it a few times a year as the seasons change but no drooping/stalling/oscillation is awesome. As for your warmup problem, try inputting the DIY defaults for your idle valve and setting it to "warmup only". It will give you a nice 1800rpm warmup and then settle to 800.
It works great for me until I turn on the lights or ac. How do you deal with this using "warmup only"?
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Old 01-27-2010, 03:51 PM   #42
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I also went back to the stock DIY settings and idle seems to be better... I may have tweaked too many things at one time and they actually worked against me.
Mostly, I don't understand what ALL the settings do or how they interrelate.

My best results seem to be with warm idle raised slightly and idle DC raised a couple of points.

This is without venturing into the aspect of AC

Sorry but I don't know the answer to your question: How do you deal with this using "warmup only"? A setting under Idle control comes to mind tho...
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Old 01-27-2010, 04:01 PM   #43
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Originally Posted by djp0623 View Post
It works great for me until I turn on the lights or ac. How do you deal with this using "warmup only"?
I don't think I understand your question. Do you mean you use mechanical idle and are having droop issues, or your idle is buttery using PWM idle control untill you introduce an electrical load?
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Old 01-28-2010, 12:35 PM   #44
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Originally Posted by Jeff_Ciesielski View Post
I've been preaching it for a while . Bells and whistles are really great and all, but in the end, a mechanically based idle with warmup assist is just more reliable and easy to set up.
I tried this today and my setup won't do it, switching between closed loop and warm up only made no difference in what the car did. It idled at 2600rpm either way. I set the warm up mode to stop at 50C clt temp but it wouldn't shut off and once up to temp (~85C) just kept doing it's high 2600-2800rpm idle.I also tried changing the idle settings back to diy defaults with no change.

The car works with it's lack of warm up idle, and will probably be better when it's not -15C out, but I'm wondering if there is something out of place somewhere causing this (or is idle control really just impossible on MSI?).
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Old 01-28-2010, 12:49 PM   #45
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Originally Posted by inferno94 View Post
I tried this today and my setup won't do it, switching between closed loop and warm up only made no difference in what the car did. It idled at 2600rpm either way. I set the warm up mode to stop at 50C clt temp but it wouldn't shut off and once up to temp (~85C) just kept doing it's high 2600-2800rpm idle.I also tried changing the idle settings back to diy defaults with no change.

The car works with it's lack of warm up idle, and will probably be better when it's not -15C out, but I'm wondering if there is something out of place somewhere causing this (or is idle control really just impossible on MSI?).
Hmmmmmmm. That is strange. Try this map. Its exactly what you gave me with 100% diyautotune settings for idle. Let the car get up to temp, then once its there, use the idle screw to bring idle down to 800-1000.
Attached Files
File Type: msq inferno94_warmup.msq (31.8 KB, 46 views)
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Old 01-28-2010, 10:29 PM   #46
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Originally Posted by Reverant View Post
With closed loop PID idle, everything is really ok except for two or three things:

1) The algorithm can't catch the A/C when you are idling. Too much load, too sudden. The idle will drop by 200-300rpm before the valve opens some more, it will then overshoot by 150rpm and then rest to the final target RPM. Btw my target idle once warmed up is 1000rpm, not 800rpm. I'm going to add an idle-up air valve to remedy this.
This can be helped by using the idle advance feature. Set it so higher load gives you more timing.

Quote:
2) When you coast down, the algorithm will try to settle somewhat higher than your target RPM (ie with 1000rpm target, that's about 1400rpm) for a couple of seconds then slowly drop down to your target RPM. Annoying, but the car never stalls that way.
This was the way the algorithm was designed (on purpose even). You can reduce that a bit by reducing the dashpot adder, then it won't go so high above your target. I did it this way to avoid stalling and to make it easier for the PID loop to smoothly ramp to the target.

Quote:
3) When you first start the car, it will first idle at 2-2.5K rpm for a couple of seconds and then drop to 1400rpm (my target when CLT ~= 5C). Probably due to 2).

Jim
You can reduce that by reducing the cranking duty.

Ken
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Old 01-28-2010, 10:31 PM   #47
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Originally Posted by richyvrlimited View Post
Many thanks Jim, that helps a lot. I've not yet worked out my rpm with valve open and closed and the corresponding DC% numbers I think that's why I'm struggling, plus the bleed valve in the TB is fully shut.

I am at a P value of 200 yet stiil no oscillation. I think once the above are nailled tuning the PID loop will be more successful.
IF your P term is that high without oscillation, set the RPM with valve open a little lower (which will increase sensitivity).

Ken
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Old 01-28-2010, 10:34 PM   #48
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Originally Posted by poobs View Post
Can some of you who don't have or have fixed the idle issues comment on my settings ?

I would like to fix my droopy idle issue and idle droop between shifts before I start playing with the new TS

I changed the following as per reccomendations from DIY via email.

Min dc from 21 to 22 ( to help with idle droop )

Fast idle "lower" 130 to 120

Slow idle ( upper) 169 changed to 140 RPM

Slow (warm) idle raised to 1000

VTPS theshold ADC from 150 to 10

Idle Activation 500 changed to 250

Dashpot settle time from 47 to 80

Dead band range 130 changed to 50

Fast recovery RPM 15 changed to 5

Slow recovery RPM 100 changed to 75


Thanks
This is the MS1 closed-loop idle settings... I'm not sure about those since I didn't write that algorithm.

Ken
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Old 01-28-2010, 10:35 PM   #49
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Originally Posted by poobs View Post
It does have closed loop.
But it's not PID though.

Ken
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Old 01-28-2010, 10:39 PM   #50
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Originally Posted by djp0623 View Post
These are the settings that I ended up with today. Idle is around 950 with no lights or ac. About 850 with ac and lights. The only I don't like is that it seems to get hung occasionally so that the idle is 1200rpm. Most of the time it is fine. 950rpm is still higher than I would like, but it is nice not to have to worry about turning on the accessories.
When it gets stuck, that's because of the PID lockout settings. Either the RPMdot setting is too low, or the MAP setting is too high (probably RPMdot). Try setting it to something like 150-200 RPM/sec and see if that helps.

As far as getting it to go back to the target better with increased load, increasing the P term will make the initial response to increased load (and decreased RPM) faster and larger. Increasing I term will get it closer to the actual targeted RPM. I would increase both until you get oscillation then back off till it goes away.

Keep in mind that if you get oscillation, you might be able to help it by making sure AFR doesn't bounce up and down when it's oscillating (which will feed the oscillation and make it worse).

To help response to increased load, use the idle-advance feature to bump up timing when load increases.

Ken
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Old 01-30-2010, 07:23 PM   #51
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Originally Posted by muythaibxr View Post
But it's not PID though.

Ken
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Old 01-31-2010, 12:59 AM   #52
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I didn't read every post on this but the idle control circuit is two parts. One is the mechanical amount of base air that is let by the throttle body and then the second is how much air is let through the IAC valve.

If the base air is not set properly then the IAC valve can't adjust properly no matter what your settings are. Try cleaning the IAC and TB area and see if that helps on the base settings. If that won't do it then you might want to adjust the base air setting, usually with a screw on the throttle plate stop. With the IAC fully closed and unplugged your car should idle slightly below the idle target with no load.

This is all IMHO and an expert can chime in and correct me.
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Old 01-31-2010, 10:32 AM   #53
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In my experience, the idle screw should be set so the IAC valve is near the middle of its travel most of the time.

Ken
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Old 01-31-2010, 12:45 PM   #54
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Quote:
Originally Posted by muythaibxr View Post
This can be helped by using the idle advance feature. Set it so higher load gives you more timing.
I enabled it but it didn't make any difference on the A/C engaging, maybe only a small difference on lighter loads.

Quote:
Originally Posted by muythaibxr View Post
This was the way the algorithm was designed (on purpose even). You can reduce that a bit by reducing the dashpot adder, then it won't go so high above your target. I did it this way to avoid stalling and to make it easier for the PID loop to smoothly ramp to the target.
Even with dashpot adder set to 0, it still settles to 1400rpm, which is really high for my taste, I would prefer something like 1200rpm (so I can have the overrun fuel cut set to 1300-1350.

Quote:
Originally Posted by muythaibxr View Post
You can reduce that by reducing the cranking duty.
The same thing happens when I burn new settings. The idle goes to 1800, the overrun kicks in, RPMs drop, CL idle kicks in and raises the RPMs to 1800 again, etc.

Jim
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Old 01-31-2010, 12:58 PM   #55
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Originally Posted by muythaibxr View Post
In my experience, the idle screw should be set so the IAC valve is near the middle of its travel most of the time.

Ken

I agree.

Also unplugging the IAC valve and adjusting the idle speed via the screw and the idle A/F cells for the best idle before fudging with the settings.
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Old 01-31-2010, 02:51 PM   #56
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I don't know how the Miata (or ford) does the idle motor. On a GM LT1 they know in the computer how many steps from closed the current valve position is and there is a range they want it to be in at idle so the IAC will work correctly. Many people have issues after doing TB modifications and have to reset this minimum air flow adjustment so that the IAC will work correctly.

Sounds like we are all hinting at the same thing. Perhaps some of these cars just need a good cleaning. That usually solves idle problems IF there are no other mechanical issues.
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Old 01-31-2010, 03:54 PM   #57
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Originally Posted by Reverant View Post
I enabled it but it didn't make any difference on the A/C engaging, maybe only a small difference on lighter loads.
What does AFR do when you engage the heavier load?

Quote:
Even with dashpot adder set to 0, it still settles to 1400rpm, which is really high for my taste, I would prefer something like 1200rpm (so I can have the overrun fuel cut set to 1300-1350.
What are your settings like? Is CL idle engaged when it settles there? (Check the CL idle indicator in the tuning software). IF dashpot adder is 0 and it still settles above your target then you're getting some air from someplace other than the idle valve assuming PID has not engaged.

If it's settling that high with PID engaged, then your I term is way too low, or your valve closed/open RPM settings are set too far apart causing the algorithm to be less sensitive than it should be. Can you post a log of the behavior you're talking about.


Quote:
The same thing happens when I burn new settings. The idle goes to 1800, the overrun kicks in, RPMs drop, CL idle kicks in and raises the RPMs to 1800 again, etc.

Jim
If overrun can kick in essentially when freerevving, then overrun needs to be adjusted. It should never kick in when freerevving.

Please post your most current msq, and a log of the bad behavior and I'll try to help correct your problem.

Ken
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Old 02-06-2010, 01:20 PM   #58
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Originally Posted by Jeff_Ciesielski View Post
Hmmmmmmm. That is strange. Try this map. Its exactly what you gave me with 100% diyautotune settings for idle. Let the car get up to temp, then once its there, use the idle screw to bring idle down to 800-1000.
Finally got around to trying your settings, they really made no difference (sorry). The idle was sitting at 3000rpm (screw set to give ~900rpm idle with no iac) prior to turning the screw all the way in which brought the idle to 2100rpm. It still idles 1800-2100 during warm up, then goes up.

Is the iac controlled by output 2? My output 2 light flashes like a strobe with the engine on.
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Old 02-06-2010, 02:02 PM   #59
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Originally Posted by inferno94 View Post
Finally got around to trying your settings, they really made no difference (sorry). The idle was sitting at 3000rpm (screw set to give ~900rpm idle with no iac) prior to turning the screw all the way in which brought the idle to 2100rpm. It still idles 1800-2100 during warm up, then goes up.

Is the iac controlled by output 2? My output 2 light flashes like a strobe with the engine on.
In the .MSQ that I gave you, is it set for warmup only?

Edit: I just checked it, and it is. Not sure what to tell you, with the exception of the frequency and duty cycles, that is exactly how I have my '92 set up. I assumed it would be the same for a 1.8 IAC. Sorry :(
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Old 02-06-2010, 04:24 PM   #60
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Originally Posted by Jeff_Ciesielski View Post
In the .MSQ that I gave you, is it set for warmup only?

Edit: I just checked it, and it is. Not sure what to tell you, with the exception of the frequency and duty cycles, that is exactly how I have my '92 set up. I assumed it would be the same for a 1.8 IAC. Sorry :(
That's ok an attempt that didn't work is better than not trying at all.

Anyone have settings that work on their 1.8?
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