poormxdad

Gents,

I was directed by 18psi to start a consolidated thread where I can put all of my new dumbass questions. I apologize to the group for getting all emotional. It's just that sometimes, this stuff doesn't make any sense, such as when I found WOT Target Voltage was working even though it was set to a value under the Alternator Control pulldown to be disabled. Or, what could the possible purpose be for MLV NOT to automatically load the tune from which the log was made? Or why when I compare tunes in TunerStudio, I only have a choice of excepting all the changes in the other tune, or no changes?

I reserve the right to post in other, existing or new threads, but will try to restrict dumbass questions to this thread.

Question(s) follow...

poormxdad

We've had a couple of rainy days and the car is up on jackstands. I was going through the tune and found this...

If I have Ignition Timing Transition Cut set to Off, but Ignition Timing Transition Return set to On (see the OFF_ON .jpg) the Ignition Timing During Over-Run(deg) box is not greyed out. Both have to be set to Off (see the OFF_OFF .jpg) to grey out that box. Can someone tell me what the functionality difference is between the OFF_ON and ON_ON screenshots?

How do the settings look otherwise?

Oh, BTW, why would the default setting for Ignition Timing During Over-Run(deg) be 36 degrees if the Tool Tip says it should be set to some small value?

Thanks,

poormxdad

Was the question too noob or too difficult?

poormxdad

I'm not feeling the usual Trubonet love...

poormxdad

I've been told my VE Table is rich, but I think it's pretty close when conditions are right.

If I'm driving on a very slight uphill grade where I have to keep just a little pedal in to maintain a constant speed, the AFRs seem fine. But if I lift just an RCH to keep my spacing on the car in front of me, the AFR might go into the low 13s. If I lift just a little tiny bit more, the AFR goes into the 10s. The log is on the highway, driving steady in normal, heavy VA I-64 traffic. I hit the spacebar when I thought I was at a proper, constant AFR. You can see the dip shortly afterwards. When this happens, I hear the recirc valve chuffing, like it's somewhere between open and closed. This prevents me from using VEAL because TS pulls shitloads of fuel when the AFR gets that rich, and when I put that little bit of throttle back in, suddenly I'm in the 16s with a little load. It's damned impossible to NOT get into a place where I have to lift slightly while autotuning.

Is the recirc valve bad? It's the metal version that comes with the Rotrex kit. Seems pretty well built. Is there anything I can do with the tune if the valve is not bad? Am I worrying too much?

Thanks,

ridethecliche

iTrader: (2)

Are you saying that you get a rich condition for a split second if you take your foot off the go pedal? Does it do it momentarily or hold at that?

(Haven't looked at logz)

thumpetto007

iTrader: (15)

Do you have "over run fuel cut" on? If you do, I don't have any other suggestions.

I am probably wrong, but I thought the VE table is just the correction factor for each load/rpm cell that the ecu uses to hit the target AFR in the corresponding cell. That's why autotune VE works. It calculates the correction factor to hit your AFR targets set in the AFR table.

Again, I'm most likely wrong.

DNMakinson

iTrader: (3)

Rich on lift is a wall wetting phenomenon. That is what AE and EAE does, as well as fix the opposite issue, lean on throttle press.

VE is for steady state. When running VEAL, it is important to drive as smoothly as possible. Y8S wrote some kind of filter that makes VEAL ignore data points when TPSDot (IIRC) is outside narrow limits. You'll have to google. But really, one or two bad points does not a huge effect have.

Keep making VEAL harder and harder as VE gets closer and closer. Then the little perturbations (look it up) mean less and less.

To Thump: look up VE, see what it stands for, and realize that it is not a correction factor, but a primary driver in Speed / Density tuning. Otherwise, yes, VEAL operates on the VE values.

poormxdad

Sir,

Are you saying that EAE is (or might be) functioning? Although I have it OFF, I have proven that although some feature might look disabled, it is not necessarily so. Go here https://www.miataturbo.net/mspnp-55/...o-start-92618/ and see Post 18.

MLV doesn't seem to have a way to check EAE functionality.

Thanks,

DNMakinson

iTrader: (3)

I'm telling you that the actions you are seeing are normal. After you get your VE table finished, then you address the lean tip-in, and rich let-off with AE.

And MLV will show EAE action, if you ask it to. At least it will when you have it turned on.

ManiacLachy

EAE and AE are used to combat wall wetting, if EAE is not turned on then it's unlikely its activating, but regular AE will be if you have it enabled. You can monitor AE% in MegaLogViewer, and you can see how big your PW spike as a result.

If VE is tuned correctly for non-AE driving then AE/EAE is used to counter the effects of wall wetting (and fuel sucked from walls) to maintain stable AFRs. If your AFRs are not stable when you drop the throttle but the cells are good under normal driving then AE/EAE is not tuned correctly.

I beleive y8s AE VEAL filtering is found here: https://www.miataturbo.net/megasquir...97/#post933498
There are other mentions of it over at msextra as well. Megasquirt Support Forum (MSEXTRA) ? Help with Analyze Live filter please... (View topic)

poormxdad

Show me. I honestly can't find it, but it's probably my fault.

DNMakinson

iTrader: (3)

There you go again. You don't need to know about EAE until you get the VE table tuned. When you have a good VE table, then we can move to other things.

poormxdad

I humbly disagree and ask you throw me another bone. I believe my VE Table is fine, especially in the area I logged. If you think that dip in the log looks like something EAE would do, I need to confirm it isn't actually working. I fight that dip in most driving conditions, and I believe you when you say that is what it looks like.

On 20 April, Phil at DIY confirmed I had found a flaw in the way they disable WOT TPS% Alternator Control in the user interface. So I am not 100% certain Wall Wetting AE is off, even though it says it's Off. I don't believe in my noobness I have found the only menu item that is faulty. That's why the Air Force has developmental testing followed by operational testing. Crewdogs always do something the developers didn't count on.

Thanks,

DNMakinson

iTrader: (3)

I can do that tonight.

I'm not sure you yet understand what I'm saying, however. I'm NOT saying that EAE would tend to cause what you are observing, but that it exists to correct what you are observing . As pointed out by ManiaLachy, and by me, you are observing a natural phenomenon of an intake manifold.

poormxdad

I did misunderstand. However, pre-Rotrex a slight lift would usually bring leaner AFRs. I know the VE table needs work in the 2900 to 3400 cruise area, but that dip makes it very difficult to tune.

I'm talking very slight movements of the pedal, but it always seems to include a change in the sound of the recirculation valve. It happens in fourth gear trying to hold 45 mph in traffic if I lift a little. At 35 mph, she appears to be in a transition point for the valve where even holding a constant slight load has the valve oscillating rapidly between open and closed. It''s worse now that I have installed the 85mm pulley.

I have nearly zero deceleration leanment under AE.

Thanks for your patience,

DNMakinson

iTrader: (3)

The EAE choices are only available on MLV when EAE was on during logging. In fact I think it has to be on when logging begins.

I don't know anything about SC recirculation valves.

ManiacLachy

I have finally had a chance to review your tune and log, so I'll give you my thoughts. Note, I'm learning as I go, I'm no professional or expert and my tune isn't perfect yet either, but I do spend quite a bit of time looking at my logs and wondering why something is doing what it's doing.

I don't think your issue is anything to do with AE. The rich condition you're describing and which occurs after your mark isn't a blip, it's sustained. And when it occurs you aren't making a quick withdraw from throttle, tpsDOT barely registers and your TPS decreases only slightly. If it were due to AE corrections the condition would be a temporary AFR change which then stabilises out. I simply believe you're rich in low load (<50 kpa) and medium RPM (3500-4500RPM). I can see you've already leaned out some cells this area compared to the cells around it in your VE, I don't think it's enough.

Take a look for yourself to see if you agree. Apply this custom search filter in MLV (go to Search > Expression Search)
Don't assume the cause of the issue simply by driving situation. ie:
Sure, that raises a flag for an issue you need to investigate, but it's not the change in throttle or the recirc valve that causes the issue, its the drop in MAP to an area of the VE table that is too rich. Spend some time driving in this region of the map purposefully and you should see the same AFRs, whether increasing throttle or decreasing. (for an example of increasing throttle use the above search filter but add in &&TPSdot > 0)

I agree your AFRs seem pretty good in general cruise, but overall your tune is rich, just look at you Min and Max AFR 1 Error readings; Max is 101%, it only ever has to increase fueling by 1%; but Min is 90% the maximum allowed by your ego settings - it's trying to pull as much fuel as you gave it authority too and I bet it would pull more if you set your ego authority higher. Search your log for places where your error is at it's Min value, those are your rich areas.

When "conditions are right" is just a small part of your VE table that's tuned correctly, a lot of it looks rich to me according to your logs.

This situation could be easily taken care of by VEAL, set it to Hard though, so it makes small changes. Get into cruise, then slowly let off the throttle, ease it off until your foot is off the pedal and TPS is 0, and the MAP will drop slowly all the way down to overrun (~15-20kpa). Do this from a few RPM points (you may need to change down a gear to hit a higher RPM at the same speed, or just find an empty road) you want to hit everything from say 2000-6000rpm.

In fact I would VEAL your whole table (outside of overrun and idle). Use the y8s filter I mentioned in my previous post (to avoid AE interference), set Min Load to ~30 (to avoid overrun tuning) and lock your idle cells. Don't try to VEAL on your daily commute, do it purposefully, go find an empty long straight flat road (industrial parks on a Sunday morning are perfect for this!). In the VEAL tab you want to make sure all of that top little map in the Status tab goes green to ensure you've hit all your cells. Apply the changes and go through this process a few times. Then log your drive home.

I hope I've made some sense here. If not or if I've made a mistake I'm sure someone will smack me down for being a n00b (I've got it coming). Something not clear? Just ask, it's your thread.

poormxdad

I appreciate your time on this. According to DNMakinson, I misunderstood the sentence below, but it does read as if AE and EAE cause rich on lift via wall wetting. That's why I wanted to make sure EAE is actually not working.

I really do not know for sure it doesn't have anything to do with AE. The car is up on jackstands right now, but when I can get her back out, I plan to play with the decel enleanment numbers just for grins.

*NOTE: Another head scratcher. The tool tip for AE states there should be "a 0 0 point in the curve so that when TPS is not changing, no additional fuel is added". However, the default curve does not come with a 0 0 point.

Although MAP is dropping into lower load cells just as you say, I do think there's more to it. I've attached a pic of the VE table after autotuning for a few minutes under the same conditions the log was taken. Going back to the dip I pointed out in the log, the AFR goes down to 10.3. Let's assume I want 14.7. I should pull about 30% fuel from those lower load cells at the bottom of the dip. That's exactly what VEAL did. Problem is, when I get into those cells VEAL leaned out under conditions where I need a little positive throttle input to maintain speed, let's say the speed limit went down and I'm now in the 2900 rpm/50 load cell, the AFR is now up in the high 16s.

The dip condition happens no matter what speed I'm at if I lift a little.

Thanks again,

ManiacLachy

I'm telling you - this issue has nothing to do with AE. Your AE might not be perfect, but it's insignificant and your VE table is the bigger problem

AE and EAE are corrections that occur when the throttle position changes rapidly. As I understand it, if the throttle is shut and you go to 50% as fast as your foot will travel the ECU doesn't have time to wait for the MAP to register then inject the fuel as there is a small delay and if we didn't compensate for the influx of air we'd be momentarily lean, and this feels jerky to the driver. So, instead we tune these corrections to momentarily inject additional fuel to compensate. Similarly, on a snap shut throttle the ECU doesn't have time to register the MAP change then reduce the fuel, so if you like you can program it to pull fuel to avoid a rich condition. Decel isn't as much of an issue as accel though. Decel is really the final piece of the puzzle.

The key thing here is that this is a momentary compensation. It is not persistent. And it is not your problem in this case. If it were we'd see a rich spike shortly after a large dip in TPSDot, but we don't see this large dip in TPSDot at all.

Let's bust out your log and some bad MSPaint skills.

Refer to poormxdad_1.jpg
The yellow circle is you in cruise with nice AFRs, EGO is at 100% and Error is insignificant. The red circles (top and bottom graphs) show a change in TPS from a sharp increase in TPSDot and the resulting AE compensation. Note that when the TPSDot is negative, there is no AE compensation, also note your AFRs aren't massively affected by these changes, the changes occur ~.5s later than the event, you go a little rich from your AE injection indicating maybe a little too much is being added - don't worry about it right now. Also note that your AFRs are nice and consistent while you're at 3700RPM @ 70kpa.

Refer to poormxdad_2.jpg
This is a moment later, you're at a lower throttle and a lower MAP, and your rich like Scrooge McDuck. EGO is trying to pull fuel, your TPSDot is insigificant and AE is doing nothing. At 3800RPM @ 55kpa your VE map is simply rich.

Anytime we see your MAP drop low, we see your AFRs go rich. It's a consistent trend in your log.

I'd advise you to try to log low MAP driving, let's say between 35-60kpa. Get a friend to look at what's happening in TS while you drive if you need to and he can tell you if you're high or not. Small throttle openings on flat ground should do it though, and hold that position - we want to capture that MAP steadily for as long as possible. This should more fully illustrate the situation.