I got '99 Problems and DIYPNP Idle is one of them
 

So I have been reading around on how to set up my idle for my 99 DIYPNP built by braineack, and it seems like the more I read the more confused I get. Right now my car starts, revs to around 1400, then drops to around 700 and as it warms up it raises to 900. I have messed around with all of my settings and I seem to be incapable of guessing what to do. Right now I do not have any of the output settings (like FIdle) enabled except for fans and vics (ALED and WLED). Something is not right. I need to set up a warm up idle of 1300 or something and then drop to 900-1000 when it gets to op temp. Here are all my current idle settings. PLEASE! Any help would be awesome!

https://www.miataturbo.net/attachmen...ine=1343071828

https://www.miataturbo.net/attachmen...ine=1343071828

https://www.miataturbo.net/attachmen...ine=1343071828

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https://www.miataturbo.net/attachmen...ine=1343071828

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open duty needs to be closer to 60%. right now that valve can only move between 21 and 26%. that's not a lot of range, and i'd expect the idle speed to never change after warmup.

bring the RPM with idle open to 2500, and with closed down to 700.

then lower your RPM targets table to what RPM you want to idle at.


Then you have to tune the PID parameters.



acutally, all your closed loop settings are all over the place, I'll have to show you what to set to later when I'm home.

the coolant-based crank duty table is what the valve opens to during/after starting. then after 6 seconds (crank to run taper) it uses the closed loop code and tries to hit the targets setup in the closed loop idle targets table. But if the settings are whacko, like yours are, it wont ever idle correctly.

Awesome! Thanks so much. That makes CONSIDERABLY more sense than what I could find elsewhere (maybe I can't find good threads worth crap). Braineack, if you could just show me how to set my PID parameters or whatever else I have WAY out of whack I would greatly appreciate it.

read through this:

Idle Control

Looks like you're using windows. If so and in order to make your life easier, <ctrl><alt><PrintScrn> creates a screenshot you can just paste into any editor etc.

Ok. So that page makes sense. The only thing I think I am confused about is "Use VSS to activate PID"? What is VSS? This is probably a dumb question.

And I can snap some pics with my phone and throw them into my photobucket app really quickly.:)

VSS=Vehicle speed sensor. Fughitaboutit.

vehicle speed sensor. you don't have yours inputting into the MS, and I don't like to use VSS for CL activation anyways.

Ok. So I read up and fiddled around with all of the settings. It seems to be finally trying to do what it is supposed to. MUCH better than before but there are a couple problems that I can't seem to get rid of.

The first thing is that it seems pretty sluggish as far as adjusting to the right rpm. Even once it is at operating temperature it takes it forever to get down to ~900. The other thing is that it seems to keep fluctuating. I have tried tuning the PID gains but I can BARELY raise them at all before it just starts fluctuating like crazy.

Do these settings look about right? And is there any setting that is outstanding that anyone can suggest a different value? Thanks for reading!

https://www.miataturbo.net/attachmen...ine=1343710394

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probably becuase not enough I term.

One thing that will help get it set, is to leave the valve open, by setting the close delay to "0". That is one less thing to get in the way while tuning. Then when you are happy with it then turn it back on.

I see you set your idle open duty to exactly 60, is that what you found through testing or just from what brain said?

Also, did you ever get to your target? If not, your min duty may be too high and no setting for the PID variables will allow you to reach your target, causing overshoots.

I really appreciate the help guys. I have not yet got the chance to mess with it yet as the current idle is definitely passable but needs work. I will be working on it tomorrow pretty extensively and I will try all of these ideas as well as reading through that idle control link more.

I did just choose 60 based on what brain said as well as the 700 and 2500 with the valve opened and closed. If by target you mean the rpm I want, yes. It does seem to hit the goal, just pretty slowly and then once it does it will eventually start fluctuating.

Here is a question unrelated to idle. Tomorrow I will be swapping my stock 99 injectors with 440cc RC injectors. What exactly do I need to change in tunerstudio to get the MS to recognize the larger injectors? Is it as simple as changing my injector flow to 440cc in injector characteristics or do I need to mess with the required fuel?

Again thanks so much for the help!

So I just got the injectors in. I looked all over the place to input injector flow rate and found nothing. So I just backed off my entire fuel map by 18 and it seemed to work. Is there anything wrong with this?

Subscribed.

Anybody?

its easier to just change the req_fuel, but that works.

req_fuel is an easier way to scale your fuel map, but it doesn't always work as it should. I changed out for some FIC EV14 775cc and changing the re_fuel was not enough to get the car to run after starting.

You also need to adjust the Idle VE, injector dead times, and Priming Pulse.