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Old 05-04-2011, 10:58 AM   #101
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you could bring the a/c switch in, then use a simple input circuit to send the signal to the table switching input.




so the Switch would be the a/c switch pin... 1Q IIRC (dont quote me on that). Then you just need two diodes and 2.2K resistor, use the 5v pin on the proto area and volia.
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Old 05-04-2011, 11:20 AM   #102
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Originally Posted by minileprechaun View Post
point to note ... megatune and tunerstudio appear to have different decimal places. i think megatune is x0.01sec and tunerstudio is x0.1sec. not sure if opening up an MSQ (from tunerstudio) in megatune will count for the difference in decimal. for instance, startup delay in my system is 0.2sec.. and you wrote you saw 0.02 sec.. is that a type, or is that how it was displayed in megatune? with that in mind .. my fast recover is 1.4sec and slow recovery is 2.1sec.

hmm.. this confused me a bit more. which way do the numbers need to go to account for being too slow or too fast? i tried changing fast recovery from 14 (in steps) down to 7 and that didn't help with my warm up RPM jumping around.
also moved the slow recovery from 21 down to 10 and up to 30 in steps. once again, it wasn't a conclusive fix. in the late afternoon, with a warm car, slow recovery at 30 gave a engine an idle that ranged from 850-950. without any spikes in RPM or AFR. But then the same setting, a couple hours later had the RPMs ranging from 600-1800 with a warm car.

Same results with ASE. I increased that in the afternoon, enough to keep the car alive after ignition. But that level was not enough to keep the car alive later in the evening.

i changed the closed loop startup delay from 0.2sec to 10sec. and it seems to work.. maybe i need it lower to help catch the engine after ignition?

attached is an MSQ i used today and a log of the car idling and some driving on that MSQ. i have attempted some tweaks to the msq .. but not enough to fix my issues yet.
You're probably right about units not transfering gracefully between Tunerstudio and Megatune.

Fast recovery should be pretty much as fast as you can make it. What you want out of fast recovery is response. You're not concerned about stability. Stability comes from the slow recovery + a decent sized window for slow recovery to operate in. Think of fast recovery as an emergency -- you're way out of an acceptable idle window. 1.4 seconds is WAY too slow for fast recovery. With Tunerstudio and 0.1 second units . . . I would set it to 0.1 seconds.

Fast recovery and slow recovery values are time units that specify how often a new Idle DC value is computed by the closed-loop algorithm. A small time means that a new value is calculated more often -- which gives fast response (note that by fast response, I mean that the Idle DC changes quickly, not that the engine is actually able to keep up with that Idle DC value). A large time means that a new value is calculated less often -- which gives a slower response and more stability. As I said before, your fast recovery should be FAST and your slow recovery should be SLOW. Also, your slow recovery needs a decently sized window to operate in (biased towards higher RPM) for closed loop to be stable.

If you're getting down to 600RPM, then you may need to revisit your idle screw setting and minimum DC. Was the 600RPM with a load?

ASE is just something you need to work on over time. The fundamental issues are:
1. When you first start and things are cold, sprayed fuel does not vaporize -- you have to enrich A LOT (to values like 5:1 or even richer!); and
2. When you first start, the MAP signal that our VE table is based upon is noisy.

So, ASE allows enrichment to a combustible mixture + artifical stability. How much and when? Wow, there are so many variables -- you just need to experiment. It helps to understand what's happening though. Assuming that you are using "Fixed then Decay" and "Fixed MAP" modes, there are two stages to ASE:

1. The first stage is simply to artifically maintain a fixed MAP value in the software for a predetermined number of seconds. During this time period, the amount of fuel sprayed is determined by the VE at the artificial MAP + a bump related to CLT from the ASE table. The artificial MAP is maintained for the "Fixed ASE/MAP Time Period."

2. The second stage is to add fuel according to CLT from the ASE table. This fuel addition fades out gradually over the "ASE TOTAL Time" period.
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Old 05-04-2011, 02:21 PM   #103
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Quote:
Originally Posted by hornetball View Post
Fast recovery should be pretty much as fast as you can make it. What you want out of fast recovery is response. You're not concerned about stability. Stability comes from the slow recovery + a decent sized window for slow recovery to operate in. Think of fast recovery as an emergency -- you're way out of an acceptable idle window. 1.4 seconds is WAY too slow for fast recovery. With Tunerstudio and 0.1 second units . . . I would set it to 0.1 seconds.

Fast recovery and slow recovery values are time units that specify how often a new Idle DC value is computed by the closed-loop algorithm. A small time means that a new value is calculated more often -- which gives fast response (note that by fast response, I mean that the Idle DC changes quickly, not that the engine is actually able to keep up with that Idle DC value). A large time means that a new value is calculated less often -- which gives a slower response and more stability. As I said before, your fast recovery should be FAST and your slow recovery should be SLOW. Also, your slow recovery needs a decently sized window to operate in (biased towards higher RPM) for closed loop to be stable.

If you're getting down to 600RPM, then you may need to revisit your idle screw setting and minimum DC. Was the 600RPM with a load?

ASE is just something you need to work on over time. The fundamental issues are:
1. When you first start and things are cold, sprayed fuel does not vaporize -- you have to enrich A LOT (to values like 5:1 or even richer!); and
2. When you first start, the MAP signal that our VE table is based upon is noisy.

So, ASE allows enrichment to a combustible mixture + artifical stability. How much and when? Wow, there are so many variables -- you just need to experiment. It helps to understand what's happening though. Assuming that you are using "Fixed then Decay" and "Fixed MAP" modes, there are two stages to ASE:

1. The first stage is simply to artifically maintain a fixed MAP value in the software for a predetermined number of seconds. During this time period, the amount of fuel sprayed is determined by the VE at the artificial MAP + a bump related to CLT from the ASE table. The artificial MAP is maintained for the "Fixed ASE/MAP Time Period."

2. The second stage is to add fuel according to CLT from the ASE table. This fuel addition fades out gradually over the "ASE TOTAL Time" period.
first off .. thanks. your explanations are really helpful and i'm learning more about how the system works opposed to just plugging in someone else's numbers blindly.

i'll experiment with the fast and slow recovery settings more. i didn't realize i could go that low with the fast recovery.

the 600rpm is with no load. car is just sitting, idling, with the RPMs hunting and searching for what's right.
I'll go back to warm-up only mode and reset the idle screw and double check my closed/minimum idle valve settings.

My ASE is fixed then decay. Good to know that it will require lots of experimenting until i get the right amount of enrichment needed.. and that it could take a higher amount than i'm blindly expecting. so i'll work more on that until the car starts without stalling! Is ASE just for the immediate act of starting the car? or to keep it alive some 2 seconds after? read below for an explanation of what my car does when i start it.

for clarification:
here's what happens.
I turn the ignition. Car starts. RPMs jump to 1800. hold for about a second. During the next second (about) the RPMs decrease to stalling point. Half the time, the engine revives itself and RPMs jump back up to 1800 and the engine starts it's RPM hunting cycle. Other half of the time, the car stalls and i have to start again.

for the above 1 second RPM decrease to stalling point... what is supposed to catch, or limit that? should the idle screw be set open enough that the RPMs don't drop below my designated idle speed? Is the RPM decrease affected by the ASE settings? Or does ASE only affect the initial ignition and the RPM for the 1 second hold prior to 1 second RPM decrease? What do the warm-up enrichment settings do? i've moved them around and they don't really seem to have an affect during warm up. but then again, i have so much going on at once that i may not truly know how what i change affects the system.
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Old 05-04-2011, 02:33 PM   #104
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Cranking/Starting and idling are two different problems. You need to work on one problem at a time. I recommend focusing on steady state idle first. Ignore your starting artifacts until you're happy with idle.

The only two idle settings that have anything to do with cranking or starting are "Cranking (DC)" and "Startup Delay." Both of these have been explained previously. I don't dig answering the same question over and over.
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Old 05-04-2011, 04:26 PM   #105
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Originally Posted by hornetball View Post
Cranking/Starting and idling are two different problems. You need to work on one problem at a time. I recommend focusing on steady state idle first. Ignore your starting artifacts until you're happy with idle.

The only two idle settings that have anything to do with cranking or starting are "Cranking (DC)" and "Startup Delay." Both of these have been explained previously. I don't dig answering the same question over and over.
gotcha .. work on one at a time. but i still may ask questions about both...
last time i used warm-up only mode to get a good idle at a certain idle valve DC at 900rpm (by adjusting both the idle valve DC and idle screw). then i switched over to closed-loop mode and set the minimum idle valve DC to match the DC in warm-up only. after getting a steady idle, it sat at about 1000rpm. at this point, i adjusted the idle screw a little to get it back down to 900rpm. was this the wrong move?

i don't mean to ask the same question multiple times.. i think my cranking DC as i can get the car to start without a problem. period about 1.5 seconds after starting that i'm now questioning. where the RPM drops after the initial crank and enrichment and how to catch it before it stalls. Is that "catching" a crank/starting issue or a warm-up/closed-loop idle issue?

i had previously adjusted the start-up delay to 0.2sec (which showed up as 0.02sec for you in megatune) and you said (0.02) was way too quick. what's a more reasonable time? i think i moved it back to about 10 seconds (100 in my msq, at x0.1sec) half the time this catches the engine during the post ignition RPM fall and half the time it doesn't. so does this mean closed-loop mode shouldn't be relied on to catch the engine post ignition? instead .. maybe need higher values for ASE? or is there were warm-up enrichment comes into play?
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Old 05-05-2011, 12:02 PM   #106
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Originally Posted by minileprechaun View Post
gotcha .. work on one at a time. but i still may ask questions about both...
last time i used warm-up only mode to get a good idle at a certain idle valve DC at 900rpm (by adjusting both the idle valve DC and idle screw). then i switched over to closed-loop mode and set the minimum idle valve DC to match the DC in warm-up only. after getting a steady idle, it sat at about 1000rpm. at this point, i adjusted the idle screw a little to get it back down to 900rpm. was this the wrong move?

i don't mean to ask the same question multiple times.. i think my cranking DC as i can get the car to start without a problem. period about 1.5 seconds after starting that i'm now questioning. where the RPM drops after the initial crank and enrichment and how to catch it before it stalls. Is that "catching" a crank/starting issue or a warm-up/closed-loop idle issue?

i had previously adjusted the start-up delay to 0.2sec (which showed up as 0.02sec for you in megatune) and you said (0.02) was way too quick. what's a more reasonable time? i think i moved it back to about 10 seconds (100 in my msq, at x0.1sec) half the time this catches the engine during the post ignition RPM fall and half the time it doesn't. so does this mean closed-loop mode shouldn't be relied on to catch the engine post ignition? instead .. maybe need higher values for ASE? or is there were warm-up enrichment comes into play?
Not ignoring you, just short of time.

I will tell you this . . . NEVER touch the idle screw in closed-loop mode. This is just like the stock engine where we only touch the idle screw when diagnostic pin 10 is jumpered. If you are changing the idle screw at the same time your ECU is changing the control valve duty cycle . . . well, I hope you get the picture.
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Old 05-09-2011, 03:24 PM   #107
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Not ignoring you, just short of time.

I will tell you this . . . NEVER touch the idle screw in closed-loop mode. This is just like the stock engine where we only touch the idle screw when diagnostic pin 10 is jumpered. If you are changing the idle screw at the same time your ECU is changing the control valve duty cycle . . . well, I hope you get the picture.
so why is idle and starting so difficult to set up?!

on saturday afternoon:
i went back to warm-up only mode to set the idle screw.
then i switched back to closed loop to get the idle working well. the best idle i could get was a steady 900-950 during normal idle. then when the radiator fan came on and stayed on .. it would hunt and rev for a couple of seconds then settle. so i thought this was pretty good. then i hopped in the car and went for a ride. at lights and stop signs .. the idle would hunt much more than when sitting at home in my driveway. then .. oddly enough. when i returned to my neighborhood (and then driveway), stopped and cruising idle was great again. back to 900-950rpm steady range. i shut the car off. waited a couple minutes and started again (with a hot engine). and it started up fine without risking stalling immediately after ignition.

then comes sunday afternoon.
took the car out again .. same MS settings as the day before. And it just didn't want to to stay alive after ignition. same problem as i've described in earlier posts .. ignition, RPMs rise with car starting and enrichment kicking in .. then RPMs drop quickly and car stalls. had to keep my foot on the throttle to keep it alive until the engine would eventually catch itself. when the car was warm .. the idle was ****. drove around some .. turned car off. then tried to turn it back on .. like the day before .. and the car refused to catch itself after ignition.

so why opposite reactions in two consecutive days?! similar times of the day, similar temperature. and why does the idle turn to **** while driving .. but fine when sitting in my driveway?!
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Old 05-09-2011, 03:29 PM   #108
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cause you're not upsetting it when sitting in your driveway. you should be bliping the throttle and turning on/off a/c everytime you change the settings to make sure it can handle load changes.


how are your AFRs at idle? what about timing? do they both go all over the place? that will upset idle.
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Old 05-09-2011, 04:24 PM   #109
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cause you're not upsetting it when sitting in your driveway. you should be bliping the throttle and turning on/off a/c everytime you change the settings to make sure it can handle load changes.


how are your AFRs at idle? what about timing? do they both go all over the place? that will upset idle.
when sitting in the driveway...

blipping the throttle doesn't upset it.
no A/C .. so can't do that
AFR = 13.8 .. fairly steady (unless when touching throttle)
timing at 14 on spark map below 1500rpm and 40kpa

only thing that really seems to upset it while sitting in the driveway is when the radiator fan goes on
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Old 06-18-2012, 10:14 AM   #110
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Old 07-27-2014, 08:19 AM   #111
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Thanks.
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