Datalog pictures...Tuning with MegaLog Viewer

[importwarrior]

i have read on the megasquirt site that if too much fuel goes in it can cause a lean out on the gauge.

maybe too much fuel and it passes out the exhaust side causing the sensor to show a spike condition.

[BaltTSI]

Yes thats what I have read, the O2 justs reads oxygen, so if it gets saturated with fuel it's not able to read anything and therefore thinks the mixture is totally lean, so yeah, it's very possibly.

 

you can put up anything you want to view in MegaLog Viewer, I just happen to see that one in the drop down menu so I put it up there for you or anyone else to see, just to see if anyone knew what it was, I don't have it turned on though, I haven't even seen a place to turn it on.

[Shelby]

engine fuel mix should only use one load sensor,,map not tps and map

[zactek]

OK, now I have a question :hmm3grin2orange: I turned my "Decel" percentage to 0 (from 20) and now I get a considerable surge anytime I step off the gas, and it's still running a little rich (even after turning the VE numbers down in the bins where the decel. occurs)

Any ideas? The hardest thing to tune for me is the off-boost and lower MAP numbers on mine, the idle and high-rpm bins are pretty dialed in...........

 

Thanks, :character0269: Zack

[Shelby]

Zac are you working on steady rpms mix, don't confuse excelleration enrichment with steady rpms mixtures , you get the steady rpms mixture set with out 02 correction working , once you have the a/f where you want it durring cruise,, you start working on the excelleration to that rpm,,this is a diff seting, now rpm excelleration mixture changes with tps changes so a slight increase in tps voltage is diff from say a mid to wot open throddle change so excelleration addition is gona be diff with a slight change to a wide change , your probley sharper then i am at this but when you are watching the a/f at a set rpms light cruise rpm and do a slight increase in throddle positon the exrichment values will be less then say if you push'd the throddle down a good bit ,lets say you are cruiseing and want to increase rpms so you push the throddle ,,what you will see is a deff swing to lean and a slow climb back to the desire'd a/f a s the rpms get to where the new tps is now ,the more the tps is move'd the wider this lean swing will be,, heck the a/f may drop out entirely and then come back,, to correct this you add fuel to the excelleration fuel add'd the more the change the more fuel ,but you also want it to cut the add'd fuel as soon as the new rpms is reach'd , so it's more fuel but a shorter duration of the event , slight tps change the shorter the event duration the more tps movement the longer the duration , be careful too much fuel cools the 02 sensor and causes a false reading , haveing the 02 correction funtion working as your makeing map changes will cause you to have a real hard time decideing exactly what you mixture changes are doing , also keep in mind 02 correction will only happen durring times of cruise and low to mid rpms range and never durring 0 vacuum and boost pressure or above 3k or so rpms , once you have you map as close to ideal as you can get , turn on th 02 correction and it will try it's best to maintain a 14.7 a/f ratio,, this you can also change , and the least amount of corection makes for the smoothest performance ,, a very large change in 02 correction will cause a surge durring the lean to rich swings

this is why the oem ecu use's a 10% correction figure , also smaller corections will alow for faster cross overs,,the change from rich to lean

durring boost the 02 will not do any fuel corrections and the map will rely on the fuel map

now the mid point on both wide and narrowband 02 can be change'd in the soft ware seting ,the narrow band normaly uses .500 volts as the 14.7 ideal a/d range (some times read as .5 volts ),now sure where your wide band is set for but on a 5 volt scale i'd guess it'd be 2.5 volts

scan tools normaly use .500 volts and .999 as full rich

changeing the ideal seting to a voltage higher then .5 volts will cause the 02 correction to use this new figure as the mid range or ideal seting to determine rich and lean,,it realy don't know any better ,but the cross over is no longer 14.7 but is lower as the voltage is set to a higher number

further the engine temp has a lot to do with just how much of an enrichment to make durring exrichment changes,,so a semi cold engine will need more fuel correction then one runing at 190f

that why you have temp seting to define what enrichment to add at what temp

this further complicate things as the engine is constantly changeing temps as your runing it

as does inlet air temps

 

why is this important,, most of your actual driveing is at cruise, well for most of us any way,,i know theres a few that have to petal to the metal durring every gear change but thats very hard on mpg these days , but if you get your cruise a/f close to 14-14.7 or so you will not be wasteing a lot of fuel for no reason.. tuning for under boost is much simpler just add fuel till your at your want'd a/f ratio

just be careful not to have any holes that drop lean as the rpms and boost goes up

[zactek]

Shelby, I understand everything you're saying......

Right now, I have my O2 correction set at 10%, the NB set at .49V, and decelaration at 0%.

I usually turn off the O2 correction when dialing in the VE bins.

My coolant temp is usually pretty steady between 180 and 190, so is the manifold inlet air temp, between 105 and 116

I rarely see the A/F drop-off completely, usually it hangs between stoich and rich (which means I've got it dialed in pretty good, right?) I'm still working on the acceleration enrichments, they're tricky 'cause I have to re-tune them everytime I change anything in the VE bins. The annoying part that in the Megatune, there's 4 of them, and it's hard to know exactly which one was active while you're driving.........one way is for someone to ride with you, and look at the PW's when you accelarate. BUT, I don't get too many chances for someone else to watch them, so I usually pick a quiet, traffic-free area and watch the laptop myself.......

Say, you're driving steady at 5Msec, and then you stomp on the gas, and it changes to 13.8Msec, then you know it was the 8.8Msec accel. enrich. bin :hmm3grin2orange:

 

What I'm saying is that when I step off the gas, my A/F doesn't drop off instantly at all, it stays at rich, SURGES, and then slowly goes down toward stoich and then lean as I'm decelarating, and that's with the decelaration fuel set to 0.

 

Zack :character0269:

[Shelby]

i was hopeing you would be able to follow what i was geting at,,my available word supply seems to get fewer and fewer as i get older but it wasn't all just for you but to any of the newer guys that may need a little refresher course

as for the decell cut off i don't have a fancy wide band but my auto meter a/f almost instantly turns off durring decell and is ultra quick to pick up changes in the 02 signal , part of that may be because i'm so lean durring cruise ,remember i'm in the 30 to 30+ mpg range under light driveing

and boost is some thing the truck sees less and less of as the price goes up lol

 

and your right with out a second person to drive it's almost imposible to do any real tuneing

Edited May 9, 2008 by Shelby

[BaltTSI]

Hey Zack, I was seeing the same thing, going real rich when I let off the gas but then coming back up slowly, so I kept turning my decel value lower and lower, and finally ended up at 0 like Shelby suggested...or was that more like insisted? well it never did get any better, and I did start to develop a surge, so I tried putting the decel back up to 35 and it actually felt like the surge went away, I know this doesn't make sense but maybe that decel value is there for some other reason? so maybe mess with that some more? or....do we know for a fact that this isn't normal?

 

As far as the accel values go....I give up! I'm in the same situation as you, no one to sit and watch whats going on, and a second problem that you don't seem to have....no time.

 

But here's what I'm going to do, I sat down and read up on this and this is what it suggested doing, completly turn off the accel bins by putting the TPS Dot Threshold to something like 30, then so you can generate some good datalog files your supposed to turn the ignition events per step to 8, the EGO step % to 3, and the EGO limit to 75, then you tune your VE table from what you see in the datalogs, just driving it steady at different RPMs.

 

And THEN your supposed go back and play with the Accel and Decel values.

 

I'm also going to try your Msec thing to see whats happing where, I was wondering about that myself...like how do you know what accel bin it's using?

 

And a question...is there a setting for if say your temp rises to a certain temp the fuel bins get richer or leaner? you or Shelby mentioned this but I haven't noticed a setting for this, except for the warmup inrichments, because I'm getting a real lean condition when I start mine back up and it's gotten hot from just sitting after shut down.

[zactek]

Hey Zack, I was seeing the same thing, going real rich when I let off the gas but then coming back up slowly, so I kept turning my decel value lower and lower, and finally ended up at 0 like Shelby suggested...or was that more like insisted? well it never did get any better, and I did start to develop a surge, so I tried putting the decel back up to 35 and it actually felt like the surge went away, I know this doesn't make sense but maybe that decel value is there for some other reason? so maybe mess with that some more? or....do we know for a fact that this isn't normal?.

 

We really ARE in the same boat :hmm3grin2orange: I've never had a surge when I had my decel at 25 or higher....I've tried everything between 25 and 60, with no real difference in how rich the A/F is when you get off the gas......except at 0 it surges, and THEN goes stoich......we DON'T know for a fact if it's normal...............I don't how much is there to mess with as far as decel.

 

 

As far as the accel values go....I give up! I'm in the same situation as you, no one to sit and watch whats going on, and a second problem that you don't seem to have....no time.

 

Don't give up....yet. And I DO have that time problem as well!!

 

But here's what I'm going to do, I sat down and read up on this and this is what it suggested doing, completly turn off the accel bins by putting the TPS Dot Threshold to something like 30, then so you can generate some good datalog files your supposed to turn the ignition events per step to 8, the EGO step % to 3, and the EGO limit to 75, then you tune your VE table from what you see in the datalogs, just driving it steady at different RPMs.

 

Sounds like it's worth a shot, if you got the time

 

And THEN your supposed go back and play with the Accel and Decel values.

 

I'm also going to try your Msec thing to see whats happing where, I was wondering about that myself...like how do you know what accel bin it's using?

 

Ok, if you know what your actual bin voltages are, all you have to do is watch your PW's when you accelarate. Say, you're cruising at 6Msec, and then you hit the gas fairly quick, and your PW goes to 16Msec, then you know it was the 10Msec voltage bin (16-6=10). Then you look to see where you have the 10Msec Voltage, (in the accel enrichment) and it might be the 15V bin, then you know that was the one. Make any sense?

 

And a question...is there a setting for if say your temp rises to a certain temp the fuel bins get richer or leaner? you or Shelby mentioned this but I haven't noticed a setting for this, except for the warmup inrichments, because I'm getting a real lean condition when I start mine back up and it's gotten hot from just sitting after shut down.

 

I'm curious about this too, and believe it or not, I THINK it has to do with the hot cranking PW.

When the car is hot, and you start it,I think it's REALLY rich, so rich that it's not showing AT ALL on the A/F gauge for a minute or 2. I noticed where the PW is when the car is hot,(about 3.2PW) and I lowered the hot cranking PW from 4 to 3.8. It seemed to run better, and the A/F showed up quicker......I might lower it even more.

The thing that gets me the most is that you're constantly chasing your own tail; You change one thing, it affects some other settings. Trial and error (a lot of error), baby

 

Zack

Edited May 10, 2008 by zactek

[slowquest]

don't forget that your 02 sensor is only accurate when it's hot. If you shut the car down, let it sit for say 15-30 minutes, the engine itself is still warm, but the o2 sensor has cooled off quite a bit. it will take it a minute or two to get back up to operating temp.

[BaltTSI]

SlowQuest, mine is taking more than a minute to come down form reading very lean, it doesn't even take this long when it's stone cold, so I think something else is going on here.

 

You may have something there Zack with the "hot cranking PW" I'm going to look into that, and thanks for the explanation of PWs and enrichments, after I get he VE table looking really good I'm going to start over with those.

[slowquest]

ok, it does sound like something else going on then. on megatune, how long does the wue light stay on when you start it hot? or does it come on at all?

[BaltTSI]

The wue light? do I have a wue light? what is a wue light? :confused0024:

[slowquest]

Warm Up Enrichment. On megatune, it should be on the bottom of the screen, should have wue, ase, cranking/running, battery, and a few others. if it's colored, it's "on". if it's grayed out, it's off.

[BaltTSI]

Ok, gotcha, this is a separate window I have to open in MegaTune, I don't see it on the main screen with all the gauges, is this the one you mean?

 

http://i188.photobucket.com/albums/z115/RL4406/5-10OCD.png

[zactek]

SlowQuest, mine is taking more than a minute to come down form reading very lean, it doesn't even take this long when it's stone cold, so I think something else is going on here.

 

EXACTLY...........something IS going on, when I turn mine on, and it's stone cold, my A/F starts reading under a minute, but if shut down and re-started when hot, takes a while to come on, that's why I'm thinking it's so rich and it takes a few minutes to clear up and start reading again.......

 

You may have something there Zack with the "hot cranking PW" I'm going to look into that, and thanks for the explanation of PWs and enrichments, after I get he VE table looking really good I'm going to start over with those.

 

Ok, I'm glad you understand what I was saying about the PW's and the accel Voltage bins.

Like I said, I noticed that mine idles hot around 3.4Msec, so I started lowering the hot cranking Pw, gonna try to get it even lower (close to 3.4Msec) and see what happens......

It might sound like I know what I'm talking about, but I'm still learning, and taking REALLY educated guesses, so don't hold me to anything :hmm3grin2orange:

 

Zack

[Shelby]

any one got any idea why theres so much pulse width diff in the MS & FIP ecu and the Hawk,, with the Hawk my idle pulse width was 1.3 ms on 700cc injs ,, now i have 780cc inj on this FIP ecu and the idle ps is like 3.5ms ,,same fuel pressure,, thats a huge diff , has to be a diff in calibration or the numbers aren't very acurate , the Hawk pulse reading is more inlne with what i have seen in other cars like GM and so on depending on inj size

[importwarrior]

whats required fuel for the hawk compared to the megasquirt - FIP?

[Shelby]

thats a darn good question,, lets see require'd fuel changes with rpm, load, engine cid, engine fuel mixture, amount of boost at any given second

so we can see the require'd fuel can be the same for 500cid as for a 150 cid if conditions are right

so how can you set a figure for require'd fuel befor any thing else is figure'd , fuel requirements change every milli sec

[zactek]

thats a darn good question,, lets see require'd fuel changes with rpm, load, engine cid, engine fuel mixture, amount of boost at any given second

so we can see the require'd fuel can be the same for 500cid as for a 150 cid if conditions are right

so how can you set a figure for require'd fuel befor any thing else is figure'd , fuel requirements change every milli sec

 

Actually, I set the required fuel first before changing anything else....FIP's ECU came with 9.8 (!!!)and ran real rich everywhere. After I set it to 8.6, I left it alone and tuned the VE bins and everything else. I've seen people use different numbers for the required fuel on their starquests, BUT their VE maps reflect that........

 

Zack

[BaltTSI]

My req. fuel is at 7.0, but does it matter? if your req. fuel is low you just make the VE table values higher, or lower if your req. fuel is on the high side...

This was my thinking in the beginning, but after reading the manual on it I think there's a little more to it....but of course the manual isn't exactly clear on everything, or you just have to read it until it sinks in.

 

I was wondering today....are we like the only one's on Earth using this setup? is there nothing else on the whole world wide web about this? would it be possible to compile a bunch of good questions and send them to who ever wrote this program? or someone who knows all about it? I thought maybe it was just me who had a hard time with the manual, but it seems that none of us really have a total grasp of what it's saying....there has to be someone out there thats an expert on this, don't ya think?

 

It's been raining for days around here so I haven't had mine out for a while, but when I do get it back out I'm starting from the beginning with just the VE table like I wrote a while back on here.

[BaltTSI]

And then I find this, does this help with your PW question Shelby?......my brain is starting to hurt :character0285:

 

Gego ego Correction ego cor1 This is the percentage correction to the fueling pulse width used to adjust the pulse width calculated from the fueling equation based on EGO sensor feedback.

Gair air Correction aircor This is the percentage correction to the fueling pulse width used to adjust the pulse width calculated from the fueling equation based on intake air temperature (IAT) density correction and the ideal gas law.

[Evil_Betty]

In addition to here, I use the Megasquirt forums

http://www.msefi.com/index.php

 

Lots of good information and knowledgeable folks on there.

 

-Justin

Edited May 13, 2008 by Evil_Betty

[zactek]

My req. fuel is at 7.0, but does it matter? if your req. fuel is low you just make the VE table values higher, or lower if your req. fuel is on the high side...

This was my thinking in the beginning, but after reading the manual on it I think there's a little more to it....but of course the manual isn't exactly clear on everything, or you just have to read it until it sinks in.

 

I was wondering today....are we like the only one's on Earth using this setup? is there nothing else on the whole world wide web about this? would it be possible to compile a bunch of good questions and send them to who ever wrote this program? or someone who knows all about it? I thought maybe it was just me who had a hard time with the manual, but it seems that none of us really have a total grasp of what it's saying....there has to be someone out there thats an expert on this, don't ya think?

 

Yea man, the manual ISN'T clear on everything.

I don't have a full grasp of all of the stuff, and I feel like I hit a wall and re-reading is just not cuttin' it anymore. :deadhorse:

There's plenty of people using a similar setup, and there IS a forum for it.

Evil Betty above has the link posted above. I've been there a few times, but can't register 'cause I'm on AOL, and all the stuff I've read I can't really apply to the Starquest. Even if I did register, I would feel like an idiot asking anything, because as soon as you post a question, they all ask you about codes, firmware, etc., which I have NO IDEA about............. :confused0024:

Phil Tobin is the guy behind all the madness, he would probably have all the answers...... :hmm3grin2orange:

 

Zack

[Shelby]

i'm not sure how it's been with you guys but over the last 20 yrs i've had a lot of friends that were into computer programing and writeing software,, after they were into it for a while forget asking them any thing ,WHY cause they could not answer you in plain english