Datalog pictures...Tuning with MegaLog Viewer

[BaltTSI]

So I'm trying to get my VE table dialed in, and everything else for that matter, but look at this picture of a portion of my datalog ( old pictures deleted for faster load) look how much the AFRs are going up and down, and at this particular moment I don't even have my foot on the gas, but it's doing this to a lesser degree even on the gas.

Notice the AFR swings from the High teens to the low teens, is this normal? I'm trying to get something that will pass emissions which I'm due for, but I don't think this is going to cut it.

Does the AFR ( the red line ) ever get any smoother than this? will setting the "Ignition events per step" "EGO Step" or "EGO Limit" higher or lower smooth this out?

I'm thinking I have another problem, maybe noise again.

Edited June 4, 2008 by BaltTSI

[zactek]

Although I'm using a NB, mine jumps even more than that and the car feels fine.

After putting in "Ignition events" at 64, instead of 32, it was less. (if you have a really good VE map, you can even put it at 72)

 

Why is your "EGO step" at 2?

Also, I think "EGO limit" should be a little higher, like 10 or 12, that way, your WB has a little more authority over what the ecu does with the AFR....

 

One more thing, why is your "EGO active above rpm" so low? I thought it had to be a few hundred above idle, mine's at 1600, that way, anything below 1600 won't be pulled to stoich, so it can be richer when getting close to idle....

 

Try those changes, do another log......... :hmm3grin2orange:

 

Zack

[Shelby]

do any tuneing with 02 correction OFF , and you deff do not want 02 correction at idle

 

the higher you set the 02 correction limit,,the taller the spikes will be ,cause the ecu will drive the mixture leaner and richer by that amount , keep in mind the ecu is makeing the mix lean and rich,and the farther lean it goes and the farther rich it goes,,the roughter the wave will be , and under boost the 02 is not look'd at at all and no correction is made durring boost ,,this is a cruise adjustment only , and the ecu is trying to obtain a mix of 14.7 :1 or what ever value is set to 50%

also the up and down lean to rich is normal, what you do not want is a real large leaning out or riching up of the mix as this will cause a surge like feel at cruise

and all the ecu can correct for is 10-12% of the amount of fuel the base map is giveing so the closer you base map is to ideal the smoother the 02 correction will be but you will always have spikes

[BaltTSI]

I'm about to walk out the door to go to work here so I'll explain later, but good info! let me set some values different and get back to you later, I'll do some dataloging on my way to work with it, thanks.

[BaltTSI]

Zack, I can't wait till you get a wide band! you really have gotten good at this, and you know how to pass what you have learned along, thanks, my AFR plot looks a lot better as you can see here, I just need to tune the VE table a little here.

I was just trying anything to see what would happen is why my EGO step was at 2, same with the RPMs, but look at the second plot, the blue arrow is pointing to a 9.1 AFR and the green arrow is showing about a 19AFR! and the BIN isn't really changing from one value to some other far different value when this happens, now the dip when it goes real rich is after I accelerated, but I don't have the accel enrichments that high, where do you have yours set now?

 

And Shelby, what do you mean by turning the O2 correction off for tunning? on the enrichments picture here what setting would that be? are you saying that by turning it off it will only use the VE table?

 

http://i188.photobucket.com/albums/z115/RL4406/DL5-1Norm.png

http://i188.photobucket.com/albums/z115/RL4406/Enrich5-1.png

http://i188.photobucket.com/albums/z115/RL4406/RichJump.png

Edited May 2, 2008 by BaltTSI

[Shelby]

if your driveing the car and trying to tune the fuel map,, you don't want the mixture to be changeing by the 02 correction at the same time , so simply raise the above rpm to an rpm below where you'l be driveing ,say 5k activation rpm ,ecu correction ocures many times a sec while it's doing the 02 mix correction and you don't want the mix to be doing any thing but what you tell it to do,,you also need to stay at a steady rpm, and while in moderate decell the injs should not fire at all ,so the 02 will go dead lean,or off untill your under power again

[Shelby]

like your seting still in neutral and rev the enginehard,, when you let up on the throddle the 02 should darn near shut off, as the injs are not supose'd to be pulseing durring decell, but will turn back on @aprox 1200-1400 rpms

[BaltTSI]

So what your saying is that there's two corrections going on at the same time? one from the tunable table (VE bins ) and the other from EGO? and to get the table tuned in you need to make the O2 EGO correction stop working, so why have both anyway?

And do you see my "Decel fuel amount % "? I remember some talk about this before, do you think that should be at zero? total fuel cut off when you take your foot of the gas? why do they include it then?

Edited May 2, 2008 by BaltTSI

[zactek]

So what your saying is that there's two corrections going on at the same time? one from the tunable table (VE bins ) and the other from EGO? and to get the table tuned in you need to make the O2 EGO correction stop working, so why have both anyway?

And do you see my "Decel fuel amount % "? I remember some talk about this before, do you think that should be at zero? total fuel cut off when you take your foot of the gas? why do they include it then?

 

I don't think it should be at 0. I have my "Decel" at 15,didn't want too chunky of a transition (from no fuel to a lot) when I step on the gas again.....plus, I don't think it's good to have the inj. turn off completely during decel.

I'm still working on my 4V and 8V accel enrichments, 'cause my map isn't fully there.....

The reason why you have 2 corrections is so that you CAN tune.....without a decent fuel map, there would be no reference point, and you'd be too lean (or rich) all the time. I think the O2 correction smooths things out and tries to keep it around stoich, BUT not too much when it's set low, and your properly tuned (which takes a while) VE takes care of the most running conditions.

Remember, when you first start out and your map is rough, you have the EGO and O2 correction set high, then, as you VE map gets closer and closer to where it should be, you slowly lower the O2 and EGO corrections........

 

Zack

[BaltTSI]

I'm still seeing a rich reading to about 9AFR when I let off the gas, and I have the decel set to 10! and I'm not getting any kind of jumping, so I thought I would try to see what would happen setting it to zero, but if this is normal and it will pass emissions then I won't worry about it, thats what I really need to know is how strict the emissions test would be, do they expect cars to go rich when you let off the gas?

[Shelby]

ok heres what happens when i go from excellerateing to decell,,my a/f meter stops reading all togather,, why because there is no fuel being inj'd no need to have any,, any fuel that is inject'd durring decell is waste'd fuel

the instant i start to near 1400 rpms the injs start to pulse again and a/f meter reads , no poping no smoke and no waste'd fuel

[BaltTSI]

Makes sense

[scott87star]

I assume Maryland uses IM240 as their emissions test? That's the dynamometer one, not what's called the two speed idle test. Either way, the test is run at specific equilibrium points, ie constant RPM, so you don't have to worry about what's happening as the car is accelerating or decelerating. The difference in the tests is IM240 samples under load with the wheels turning where two speed idle is just the motor at two RPM points, no load.

 

Scott

[Shelby]

at nearly $4 a gal for gasoline it makes no sence what so ever to be dumping it out the tail pipe for no reason at all, so turn the injs off durring decell your pocket book will love you for it so will your spark plugs and rings

[BaltTSI]

Thanks Scott, thats what I needed to know, it is the dyno test for older cars, do you happen to know what RPMs they test at?

[Lusion972]

Balt...if you know anyone with a shop that can provide you with a receipt for work done over 800 dollars I think it is you can just bypass the emmissions if you fail. I used to that every 4 years in Maryland that or I would give the guy 50 dollars to pass my car...depends on who was working.

[BaltTSI]

No, I don't really know anyone at a shop, since I do most of the work on my cars myself, but I'm actually very close to having a good looking plot that I think should pass

[scott87star]

Texas does it at 1500 and 2500 RPM.

 

Scott

[importwarrior]

i believe las vegas did their test at 1000 +or - 300 RPM also 2500 +or- 300 rpm.

[BaltTSI]

Ok, here's my latest, the only thing I'm worried about is this going from real lean to real rich situation, the blue arrow is showing about 21AFR, the yellow arrow about 9AFR.

Now I do have the deceleration set to zero, I have been all over the place with the acceleration values, I'm still trying to find something that works, the white line is the gas pedal, you can see when I push it goes lean and then the accel seems to take effect and it drops fast to the lean side, and then you can see where I increase the gas at a more steady rate it's still spiking all over the place, the RED line is the AFR, any thoughts?

 

http://i188.photobucket.com/albums/z115/RL4406/5-5-08.png

Edited May 11, 2008 by BaltTSI

[zactek]

Ok, here's my latest, the only thing I'm worried about is this going from real lean to real rich situation, the blue arrow is showing about 21AFR, the yellow arrow about 9AFR.....( the arrows aren't showing up for some reason )

Now I do have the deceleration set to zero, I have been all over the place with the acceleration values, I'm still trying to find something that works, the white line is the gas pedal, you can see when I push it goes lean and then the accel seems to take effect and it drops fast to the lean side, and then you can see where I increase the gas at a more steady rate it's still spiking all over the place, the RED line is the AFR, any thoughts?

 

http://i188.photobucket.com/albums/z115/RL4406/5-5-08.png

 

I noticed you lowered your "accel enrichments" a lot since I last saw them......

You also have the "accel time" at .3 ms, I have mine at .1 ms

I remember reading something in the manual about lowering your "accel time" and bumping up the "accel enrichments" Mine are much higher than yours, especially at 4 and 8V.........

That is a big AFR range on yours, mine are always between 12 and 17.

 

Zack

[BaltTSI]

Yeah, I was trying the to see if making the times longer would help, longer but less volume, because the spike seems to be so short like the extra accel isn't going on long enough, bad theory?

[zactek]

Yeah, I was trying the to see if making the times longer would help, longer but less volume, because the spike seems to be so short like the extra accel isn't going on long enough, bad theory?

 

Just a thought..........Maybe when you see that DIP, you're actually going really rich, not lean.

Then, as the car starts going, your A/F's show rich. I would try lowering your "accel time" to .2 ms, and .1 ms, and leave the "accel enrichment" alone.

Take a look at what the PW's on the injectors are doing from a datalog.....If they spike up, there's no way you're going lean, it just shows up that way from the O2 because it's really rich, then straightens out to actually showing up rich. Don't know if it makes any sense to you.......

 

Zack

[BaltTSI]

Good thought Zack, I do remember reading about that so yes, it makes perfect sense, so I do see the PW spiking up at the same time( red line at the bottom) but how do you connect that with being rich? and this view is after I did turn the accel time down to 0.2 and I even lowered the Accel Enrich bins a bit, but it still spikes lean, so maybe I'll keep lowering the enrich bins even more untill I see something change, although they look pretty low now don't they? but just by the feel of the car I think it's better, it's not lurching as much during this spike, in fact I don't think it did at all, although I wasn't really pushing it....yet

BTW what is the TPSecc? (orange line) I know the TP part but the secc?

 

http://i188.photobucket.com/albums/z115/RL4406/5-6-08.png

[zactek]

Good thought Zack, I do remember reading about that so yes, it makes perfect sense, so I do see the PW spiking up at the same time( red line at the bottom) but how do you connect that with being rich? and this view is after I did turn the accel time down to 0.2 and I even lowered the Accel Enrich bins a bit, but it still spikes lean, so maybe I'll keep lowering the enrich bins even more untill I see something change, although they look pretty low now don't they? but just by the feel of the car I think it's better, it's not lurching as much during this spike, in fact I don't think it did at all, although I wasn't really pushing it....yet

BTW what is the TPSecc? (orange line) I know the TP part but the secc?

 

http://i188.photobucket.com/albums/z115/RL4406/5-6-08.png

 

If you see the PW graph going up, it means the injector is opening, and staying open....logic dictates that if it's open, fuel is going in, and it can't be running lean........BUT, get too much fuel in, and it READS lean, at least that's what I'm thinking :confused0024:

The TPSecc, I have no idea, I've never noticed it on mine. I think that's used when you specify enrichment according to your TPS, not your MAP sensor, is it possible that you have them BOTH turned on (I think that's not reccomended, if it's even possible)???

Keep at it.......... :hmm3grin2orange:

 

Zack