IAC Closed Loop Question

[ironwill11]

Got to do some work today, and realized part of my problem with the idle into and out of gear. It actually takes a few seconds for it to enter closed loop, then the valve starts moving. It is not really that the valve is moving slowly, but it doesn't recognize the load change quickly. I tried lowering the load threshold percent but it seemed to have no affect. I even tried taking out the PID delay but the software only allows a minimum of 2 seconds for PID delay. It does this both putting it into gear but you can see it easier when I take it put it into neutral. The rpms go up, the CL indicator light on the bottom of the gauge panel goes off, then a couple seconds later it comes back on and the start coming back down to the target idle.

Will

[turbo conversion]

Post your current msq and data log.

Get engine to operating temp while driving and then take the log.

With transmission in neutral let TS enter closed loop and achieve target rpm for about a minute.

Before you put it into gear tap the space bar, this will put a red stripe on the log.

Let it go to target rpm in gear and let it idle for about a minute.

Just before you put it back in neutral hit the space bar twice.

David

[ironwill11]

Post your current msq and data log.

Get engine to operating temp while driving and then take the log.

With transmission in neutral let TS enter closed loop and achieve target rpm for about a minute.

Before you put it into gear tap the space bar, this will put a red stripe on the log.

Let it go to target rpm in gear and let it idle for about a minute.

Just before you put it back in neutral hit the space bar twice.

David

Interesting I never knew that about hitting the space bar.

Well I hit the space bar and immediately shifted from neutral into gear with at the single red line. Then at the double red line I immediately shifted back into neutral. I can take a video of it and post it on youtube if it helps. You can see that it sits there for a second or two before it recognizes the change in load and rpm. The movement of the IAC looks pretty smooth and fast to me. Everything else seems pretty stable.

This is the MSQ:

2017-05-24_23.49.32_Red_Line.msq

This is the MSL:

2017-05-24_21.21.10_Red_Line.msl

Will

[turbo conversion]

Give this a try.

David

[ironwill11]

Give this a try.

David

Ran a datalog with the new MSQ. The truck/engine seem to run much smoother when put into gear. Still seems to take a while to notice that the MAP/RPMs changed. I am not sure what could cause that since it is in closed loop mode from the time it starts. Also I am not sure what RPM spike at 69.323 seconds was about. I was letting it idle and it was almost as if it did a burn for a second.

This is the first datalog I did:

2017-05-27_20.11.30_Red_Line_d.msl

The second log to see if I could repeat the results (the afr responds well, just doesn't seem to be consistent or closely precise- seems a TBI thing):

2017-05-27_20.14.43_Red_d2.msl

MSQ used:

2017-05-24_23.49.32_Red_Line_Dave.msq

Will

[turbo conversion]

It is getting better, try these changes.

David

[ironwill11]

It is getting better, try these changes.

David

Not exactly sure what changes you made with that last MSQ. I noticed that It did stay much closer to the target idle but had some weird spots during warm up. Once it got to about 800 rpm it started to oscillate. Then the idle would only go down to about 720 rpm, but it then lost the oscillation, but would not get down to the target idle at 675 rpm. I tried to grab a datalog as fast as I could. I was wondering if it was the increase in the Proportional gain.

2017-06-01_18.51.09_Oscillation.msl

Will

[turbo conversion]

A few more changes.

David

EDIT: add msq

[ironwill11]

A few more changes.

David

EDIT: add msq

So after having to have my laptop fixed, I got to do more testing.

The datalog from the first MSQ you sent (try first):

2017-06-08_18.43.18_try_first.msl

It didn't have as much idle hunt, but the AFR was thrown way off. Really rich (around 12). I wanted to try the second one before trying to tune the VE table.

The datalog from the second MSQ you sent (try second):

2017-06-08_18.46.18_Try_second.msl

This one had a little idle hunt, but for some reason it seemed to straighten out when I clicked to start the datalog. The AFR was much more stable and in range during this one. Some interesting things happen though. When shifting out of gear into neutral (double red line) the rpms increase, and then there is a sudden increase again real quick. Then it starts bring the rpms down.

Will

[turbo conversion]

Try this.

David

[stanglx2002]

I am running into the same issue and just thought it was just an automatic transmission issue and couldn't be tuned around.

Could you please post what the changes you are making, so I can try addressing my issues as well?

[ironwill11]

Try this.

David

I ran the file that you sent on 6/19; I could not verify the changes made 100%; the file had the same name as the last one when I downloaded it. TS was showing me that the where in the VE table but the Spark advance was steady at 16 degrees the entire time.

This the datalog from running the file you on 6/19:

2017-06-23_20.24.12_New_File.msl

And this is the tune file that I used:

2017-06-03_15.56.54 %281%29.msq

The single red lines are shifting from neutral to drive and the double red lines are shifting from drive to neutral. It still takes some time to change but it is better. When you shift out of gear the rpms increase to about a 1000 rpm and stay there instead of increasing again like it was doing last time.

Will

[turbo conversion]

What firmware are you using?

David

[ironwill11]

What firmware are you using?

David

I have the MS2 extra firmware 3.4.2 (board is 3.0.22).

Could there be an issue with my output? I believe when I purchased me MS2 I wound up getting an older model that may have sat on the shelf for a while. It was sent to me with instructions for the Megamanual, so my circuits were build using the megamanual. It wasnt until the nice folks at DIYautotune showed me the upgrade to the extra and firmware update did I have a problem with the out put. After the firmware upgrade I had to use a different output from what the current manual suggests because of the circuitry (injectors would stop firing once the engine started). I don't think that there was any difference with the spark output though or if that would affect the advance you are referring to.

Will

[turbo conversion]

No it is in the firmware, I will have a look at the log and msq tomorrow.

I will do some reading on it for your firmware as it is different than mine.

David

[ironwill11]

No it is in the firmware, I will have a look at the log and msq tomorrow.

I will do some reading on it for your firmware as it is different than mine.

David

Would it be easier to switch firmware to something better?

[turbo conversion]

3.4.2 is the latest released firmware, I am using 3.2.5.

I may eventually up grade to 3.4.2 but for now 3.2.5 has all the features I need and is running awesome.

For now I am lazy and don't want to do any retuning (some retuning required if I switch firmware), I just want to drive and enjoy.

David

[turbo conversion]

One more time, let me know

David

[ironwill11]

One more time, let me know

David

It seems like it recognizes the load quicker and adjusts for it; however, when you go back into neutral and remove the load it tends to find itself in a cyclic idle hunt (It starts to develop an idle hunt, it reaches a peak and straightens out, then starts over again). The rpms don't go up quite as high when it goes back into neutral from drive.

Here is the datalog:

2017-06-27_11.28.15_Will_IAC.msl

However, This datalog is from before any shifting occurred. You can see a pretty steady rpm and IACV after warm up (I stopped this datalog because I was not sure if it recorded the red line - although it seems I am wrong.):

2017-06-27_11.27.06_Will_IACV.msl

Will

[ironwill11]

3.4.2 is the latest released firmware, I am using 3.2.5.

I may eventually up grade to 3.4.2 but for now 3.2.5 has all the features I need and is running awesome.

For now I am lazy and don't want to do any retuning (some retuning required if I switch firmware), I just want to drive and enjoy.

David

Yeah I know exactly what you are saying. Quite frankly, if I ever get this thing running right I don't know that I would upgrade firmware either. I actually have MS just so I could drive it. Although, through the process of learning about MS I think I did figure out the original issue.

Where do you get information about firmware differences? I was looking on the internet; although, if I found something I fear that it would be over my head as I do not know anything about code.

Will