Doober

Ok, I set the OpIdl flag for now, I'm just a little concerned I'll still need to lower the pressure so I can get a reasonable a/f to pass emissions. So far it will idle to about 12:1, but injector DC is down around 2% and it doesn't idle quite as smooth.

As far as it not learning, I meant the time it takes for it to start learning. It does do corrections fairly quickly... while I'm doing a learn I keep the WB reading up, and the WUD is set to watch the actual VE corrections.

Doober

I hadn't really looked at the VE table of the latest learns... VE was way low, so it's been to the point of stumbling hard, and eventually it will stall when it's cold. I also found out why the dead spot, VE was down to 9 at one point on the table, I'm sure it's due to the fuel pressure and it keeps trying to compensate for the rich a/f. I think I found my low VE portions of the table now that I've done some learns, they weren't as easy to find the first 5-10 or so.

Ronny

iTrader: (1)

What is maximum duty cycle you see at higher loads?

Cflick

Not so sure.

Unlike you, my WB shows good. Close to 14.6 or so for the following... ( knowing that spark advance can affect this more than we sometimes care to admit )

My rig has a pair of 80#/hr injectors running 25 pounds fuel.
The injectors go erratic below 3% duty cycle, almost always throttle lift.
I have VE entries as low as 7% and as high as 90%. ( a good range, methinks ) (( are you sure your dead spot isn't AE ? ))
At a 650 RPM idle, the injectors are running 3-4% duty cycle, on the hairy edge of erratic, right where I want them.

Now that you've "made me look" I'm seeing dead steady idle fueling, and it appears MY idle issues are almost all coming from spark compensations.

Some things become very apparent when you graph the data against each other.

About emissions tests.....
I KNOW my left cat is burnt out completely. ( yeah, there's a story ) Took it through testing as a "what the h%$# ! If it passes, great, and if it fails, that's expected."
It passed with emissions at about 1/2 the legal limits, although that's ten times what it traditionally tests with good cats. They did sniff the left side, with the bad cat.

Doober

What are the limits up there? Out here it's like 220ppm.

Cflick

About the same.
It tested something like 112 with a bad cat, and traditionally something like 10.?
Any more precise and I'll have to go look it up.
Here, they only look at HC, CO, NOx, and CO2. ( and gas cap pressure )
OBD2 they just plug in and verify the check light isn't burnt out, but test nothing.

Doober

Sounds like the testing out here too. I think the engine just needed to warm up, because after several more learns, it would idle at 15-16:1, but it starts getting a little erratic and almost stalls, possibly similar to what you're talking about. DC% drops to 2%, and pulse width goes as low as sub-1ms, and that's when it starts getting the jitters.

I also did a short WOT run to see how the a/f is up top, and while not perfect, it's decent, though a little bit rich. Peak DC I saw was 60%, and that was a 13.1:1 a/f... from what I've calculated it sounds like the engine is only making around 300hp, but that may very well be expected with running TBI heads... I may have needed to open them up a little more. Regardless, it makes a ton of torque and pulls extremely hard from idle up through at least 3000rpm, even with 3.08s and 28" tires on a 3500-3700lb. truck.

VE learns seem to be coming along ok, I have a range of somewhere between 50-70kpa and 1400-1700rpm that seems to want to flip-flop, I think it's because it was while I was driving on the expressway and it went through that range a lot during cruising and deceleration... I know it's lean for sure though because at cruising speed I can press the gas and a/f climbs to 20+. Many of the other areas are getting closer, the truck is much more drivable now.

Cflick

My philosophy is to run the learns, ignoring PE, AE, and decel, until I start to see corrections ranging only 2 percent or so, OR corrections opposite to what it did last time, then move to other things, possibly coming back to learns when I believe I'll be driving in ranges previously not available, like towing a trailer which causes much longer sessions at steady state. 2 or 3 percent is close enough to be in "normal" expected tolerance, I believe. Weather changes, and such.
I'd expect that, if AE is off. If it stays there more than a second or so, then the VE may still be off, and I go back out and try to get a sustained learn at that RPM and MAP on steady state throttle if at all possible. Find a big hill, drag the breaks. ( after confirming that those lean spikes are repeatable )
Having played with it more than some, I tend to trust Bob's code more than my own eye, gut, feeling, whatever. Machines are not influenced by emotion, or gut feeling, and don't overlook things as a rule.
I've also gotten more feel for the whole thing by running learns from logs, and not so much from down the road. One can pause the playback, and take a closer look at what was going on, get some insight as to why it's doing what it did. Also watch for VE corrections in opposite directions at the same conditions, then split the difference and not change that range again until I start seeing consistent corrections in that range, due to a timing adjustment, or whatever.
The WUD display shows WAY to much data for my one still functioning brain cell to digest in real time. Usually takes me days to digest and analyze an hours worth of log.

slowgta

Port and fuel pressure:


The new EBL software has a utility for calculating BPC VS VAC for a vacuum referenced FPR but that option only available if you select TBI, not for port. Why?

I have a port system and use a VRFPR. Is this a problem? I run 50 PSI and the pressure swings from 45 to 60 in the data logs as the engine vacuum changes. I have been having trouble with my learns as far as getting the last few percent to dial in, one time it adds a little fuel, next run (ten minutes later!) it pulls it, I've really been chasing my tail with it and am now wondering if the VRFPR is the problem.


Thoughts?

Ronny

iTrader: (1)

Is ther an "update" rate to slow down large changes-swings in BLM changes or Integrator?

I would expect changes when barometric pressure or envionmental ait temps change.

ownor

iTrader: (5)

slowgta, if i'm correctly informed EVERY application where the injectors are behind the throttle plate needs a vfpr because of the difference of ported vacuum / manifold vacuum and the corresponding difference of what the injectors "see". but i'm sure rob will chime in here to clarify

RBob

iTrader: (1)

On a MPFI system with a VRFPR, this is done to maintain the same pressure differential across the injector. By doing so the injector flow rate is consistent.

This is how the TPI set ups are run. Later systems such as the LS1 use a return-less fuel system with a set fuel pressure. With these the ECM compensates for the varying injector flow rate.

When the VE Learn is only moving a few percent from 0%, you are good to go. The fueling is always going to be slightly changing.

RBob.

Doober

I just thought I'd give a short update... turns out I did have the MAP on a ported vacuum connection. I've done less than 10 learns from the tune I originally used for the first startup and probably 85-90% of the part throttle/cruise areas are already down below 10% in corrections.

Doober

Another question that came to mind... I'm not 100% sure I have the MPG injector flow constant set correctly. Would I set it for its new flow rate (with higher fuel pressure)?

Ronny

iTrader: (1)

From Intro To Tuning :

INJ - MPG Injector Flow Constant:

The WUD uses this value for the trip display calculations. Set it close to the required value. Then as the tune comes together do some actual testing and make minor corrections. Even if this isn't done, it may still be used as a relative value to gauge tuning for increased fuel mileage.

Injector Flow Rate and Engine Displacement:

This will need to be changed for any change in engine displacement, change in fuel pressure, or a change in injector flow rate.



So the answer is yes. Fuel pressure is mechanical so that value varies with FP#.

xch3no2

Yes.

EDIT: lol now my answer is redundant, sry Ron.

Cflick

Since this is only used to display MPG in the trip screen, make a good guess and get it in the ballpark.
Compare to actual pump mileage over a couple tanks.
Adjust it up or down by the percentage of error it displays compared to the pump.
Got mine within 1/10 MPG of actual in two adjustments that way.
Note that my injector flow rate calculates to 108 lbs/hr each, the MPG constant that gets me actual real MPG is 129.80, so either my injectors flow more than I think, or there are other variables at work.

Cflick

Depends on whether you're tuning for theoretical calculations, or for your collection of parts, and what YOUR engine wants.
If you're tuning your engine for what your engine wants, then you adjust the VE tables for measured exhaust AFR, regardless of what the injectors supposedly flow, or fuel pressure, or anything else for that matter.
As long as your combination of parts can deliver consistently repeatable results within the operating range, ( as do mine ) then you don't *need* a vacuum referenced regulator.
You need adequate fuel delivery at the high end, within the upper duty cycle limitations of the injectors, and not excessive at the low end within the duty cycle limitations of the injectors. If both of those conditions are met, it doesn't matter if fuel is delivered from a coffee can sitting on the hood by gravity feed, or a high precision vacuum regulator and speed controlled variable pump.
Sure, due to MAP my injectors "see" higher differential during decel, and lower differential during hard acceleration, exactly the opposite of theoretical optimum, but as long as they stay consistently repeatable and controllable, who cares ?
Remember your objective. If it's precision control, then by all means you need an VAFPR. If it's engine performance on the road or track, then maybe you do, and maybe you don't.

Cflick

Bob and I agree. The "problem" is that you're done as far as massaging the fuel tables, not that there is a mechanical "problem."

If you can tune for 100% of the time 128 BLM, 0% VE learn corrections, then something in your approach is very wrong !!
Tomorrow, the weather will be different, and your fuel map WILL be off by a couple percent. It doesn't need tweeked. That's why the BLM exists, to compensate for weather, going up and down hills, ( barometric changes from the top of the hill to the bottom ) and other expected day to day ( or minute to minute ) variations in temp, air pressure, fuel quality, etc. etc.
If your VE corrections are within 2 or 3 percent, up or down, or both, you're close enough for all realistic purposes.
Once you get as close as you are, up one time, down the next, your next step would be a l--o--n--g drive, maybe 150 miles or so of mixed driving, on an "average" day, with the final VE Learn encompassing the whole drive, then leave it alone until there is a valid reason to re-address it, such as timing changes, or different injectors, or some thing like that.
The beauty of the EBL system, is that this can be accomplished "autonagically" without spreadsheets, calculators, hundreds of runs and corrections, through the VE Learn, and by a variety of ways, including wide band, narrow band, real time down the road, or from recorded logs, or any combination of the above.
By using the EBL, you have it SO easy !

freaky

i have one more quick question . will the aem wideband gauge work with this or do i have to buy the one on the product page on "dynamic efi "

RBob

iTrader: (1)

If the AEM has a linear 0 to 5 volt output for a data logger then it will work.

RBob.

freaky

cool ...

Doober

Ok, I'm getting into the fine tuning stages of the truck... it runs and drives great, now I'm down to the little things. I've encountered an issue with the idle I can best describe as a 'rolling' idle. It will rise to 1000-1200 rpm, then drop to almost stalling, and repeat.

Cflick

As above, in my case, idle spark compensations were the cause.
Cutting them to 25% of what they were steadied out my idle 90%.
Look at the IAC. Is it chasing the roll, leading, or unchanged ?
Look at fueling. I look at injector duty cycle.
Look at spark timing.
Pay special attention to the one that changes just before the RPM changes.
( assuming it's one thing, and it probably is )

RBob

iTrader: (1)

Check if it is going into async injection mode. If so then set these to zero:

INJ - ASync Transition PW - TBI Only

Sounds like it is bouncing off the stall saver.

RBob.

Doober

That's just what it looks like it's doing too. IAC opens up, spark advance increases and duty cycle jumps. I changed the idle compensation in the BIN, haven't had a chance to flash it to test it 'cause my laptop is at the girlfriend's

skerlock

Hi all, Im very new to this. Ive had my EBL system installed since last saturday. I have a ton of questions but Im looking for the basics of file management at this point.

1. What Is the Tunerpro File (ebl_v31.XDF That came in my EBL file folder). Does it set the parameters for what sensors are being used for my computer?

2. Whats the best way to manage the .XDF files?

Im looking for the basics on File management in Tuner-Pro and EBL WUD programs.

Thanks,

SCOTT

thmpsn70

Scott, goto http://www.dynamicefi.com/
on the top it says home products information ...
click on information then toward the bottom of the dialogbox you'll see introduction to tuning 1 read that for the answer to question 1
question 2 was a good one I am anticipating some ones answer. Timmy

skerlock

thmpsn70,

Thanks for the reply. I have been over that link and Im looking for a more detailed explanation on the .XDF file. It is possible Ive missed it. I understand its a definition file. Curious on why would I need multiple .XDF files, if i even do.

As far as my management of files go I'm good with The .BIN files but am more concerned with the .XDF files.

Scott

Doober

Cflick thanks for the tip. I brought compensation down to about 25% of what it was and it idles a whole lot better, still seems to be doing the same thing, though on a very small scale. I haven't really watched it too closely yet (standing in the muffler shop having the exhaust done), but I plan on trying to straighten it out today.

Doober

Turns out my idle issue was also largely caused by the VE table being off. I've had to mess with it manually instead of doing learns (because it just seems to ge worse & worse via learns), and it's slowly getting better. I still have some low-MAP (correct? low MAP: high vacuum?) learns to do, mainly for deceleration because it's going quite lean and tends to stumble and buck as it tries to stay running sometimes. Other than that drivability has been great.

Cflick

The short version is that you need the XDF only to tell TunerPro how to interpret the bin file, so that it displays the correct information from the correct locations in the calibration, along with the correct labels.
You will have no need to modify the xdf in any way. Rbob will supply a new one whenever the code changes enough to require one.
If your version of the EBL itself doesn't change, then you don't need another xdf.

If you are running other ECM's, then you need the appropriate xdf for the code in those ECM's.

skerlock

Great, Thank You... Heres my next question.

Ive done a pretty good job with changing my VE tables in conjunction with the VE learn. This engine is running the best it ever has and being it has 7,000 miles on it I'm well ahead of the game. So, The thing id like to do next is to be able to set-up adjustments when my system is NOT in closed loop. More precisely, I want to get a handle on the COLD starting (mine needs some accelerator still and feels like its running on 1/2 the engine for trhe first minute or so. Not much a problem at 35 + degrees but when its below (35 is just a ball park.. I'm in MONTANA so 0 degree days are common right now) I need to set some better parameters.

I saw the settings showing Idle vs. temperature adjustments. Are the temperature settings in Celsius?

Plus what do I need to adjust on the low end for cold Non-closed Loop running?

Scott

Doober

Since my phone decided to be stupid I'll retype this...

One of the things to look at if it's having trouble starting is the CRANK - Prime PW ("This table is a cranking PW adder based on the engine coolant temperature. When the engine is first cranked the first two injections (TBI) or the first one injection (Port) has added to it the value from this table. This provides an initial pulse of fuel to aid in starting."). It basically says how much of a 'pump shot' (like when you hit the gas on a carbureted engine) to give the engine when it's cranking. It may need more or less, I somehow set mine way too low (probably before I realized what I was doing ) and the truck wouldn't start at all after it got past 200º or so.

As far as closed loop, there are a couple flags you can set, along with setting the closed loop CTS value very high so the computer won't go into closed loop (Option word 1: OpCrs - Enable open loop fuel during cruise, and OpIdl - Enable open loop fuel during idle; also Closed Loop - CTS Threshold: Minimum engine coolant temperature before closed loop fueling is allowed). Those will keep it from going into closed loop, earlier in the thread RBob also mentioned a couple other things to set, one was to disable EGR, but I'm not sure what the other was.

For ºC, I'm not to sure of that either. I just made a small spreadsheet with ºF-ºC and ºC-ºF formulas for a quick conversion.

liquidh8

Hey all, haven't been on the boards in a while. The military and work keep me pretty busy. Doober, glad to see you posting on here, a wealth of information here!

RBob, with the EBL, which fueling schemes are used? Is it batch fire, bank to bank? Just curious as I am still looking to use the EBL on my turbo Buick. Just wondering if this set-up would be better than a stock 7148 ECM with a TT chip.

I have the EBL classic on the chevy, though I haven't been driving it for a year, and I always loved it! Trying to talk a friend into getting it for his TBI retrofitted Jeep.

liquidh8

Ahhh, I see it, I had to go back a few pages! YES!!!!

Ronny

iTrader: (1)

Low MAP doe equal high vacuum.

When the %TPS hits zero I believe Learn does not take place. Watch the closed loop flag turn off in WU. That tells you Learn is off. I think there may be a Learn flag as well on WU. I forget. Those colums in 20 MAP I manually adjust. In fact I error on rich. I think I put them same as 25 MAP column. Looks like you need more fuel at low MAP.

Regardless with a deacceleration it will always shear the wettness on the manifold walls leaving it dry when you get back on gas. This happens to be at return to my house. I have a long downhill grade and a L turn. I am 45 MPH to 10 MPH when I push on pedal(manual trans) in 2nd gear and find a dry manifold. To overcome this I added to AE-TF to help out. Same on AE-TPS at low % TPS one could add more fuel. That plus add fuel to low MAP VE as stated.

Cflick

Since water freezes at 0C and boils at 100C, I guess at what's between.
Generally close enough for most practical purposes.
My 195 thermostat should be "about" 95C or so, more or less, and I can go into closed loop "about" 40C, more or less. Stuff like that, without running an actual conversion.
For anything specific, I do the conversions. C*1.8+32=F

liquidh8

'8253? is this 1228253, all I can find is it is from 89-91 pontiac/buick/olds, with the 3.8/3800? I wanna start looking in the junkyard now for some cores for when you release the EBL for it.

xch3no2

Yes.

"Plus what do I need to adjust on the low end for cold Non-closed Loop running?"

Open Loop-AFR vs RPM & VAC are the basic VE tables.
Open Loop-AFR Multiplier vs CTS will be your temp modifier.

skerlock

Help Please,

I have added a higher pressure Fuel pump (190 LPH )
I am running the following:
383 Stroker
670 cfm Holley Tbi (Injectors are running at 22 PSI. @ 85#)

The BLM will not drop below the 140 or so in the higher ranges of the high speed table. Every time I do a VE learn it wants to raise up the values.
(see Highspeed VE)

Wouldnt I need to lower the VE tables to get closer to the 128 BLM?
I did manually lower the tables and lost power.The BLM still didnt move much. got to 135+. I lost power and looks like my knock sensor went off.

I am pretty happy with the low speed although my idle seems rich.

When I lower the ve on the idle it doesnt like to idle and I start get surging

I know I need to do some smoothing I will do that once I am going in the right direction.

Ronny

iTrader: (1)

I dont understand how you can Learn at 80-90-100 MAP at RPMs 1700-2000.

Same with VE2 at 2200-2600 at 100 MAP. Those cells I needed to manually adjust.

Your BPC looks OK. I suspect you have an exhaust leak! That was my case a few years back. VE went over 100.

Idle surge may be due to injector size/FP. You may need to run a VAFPR to improve idle.

What is the pulse width during idle? Are you idleing "synch"? Did you disable asynch?

A reduction in proportional gains may be necessay if you have not already.

Doober

Bleehhhhhh... I change my answer lol.

skerlock

I am very new at this so more details are need here please


I have no exhaust leaks, although I just had the Cat pulled off. Engine has 7000 miles on it with new exhaust manifolds

I'm sure its not learning im really concerned that my BLM is 140+


Thank you for all patience as i learn this

Scott

Doober

sPW and aPW are your synchronous/asynchronous pulse width... with what you have (I have a similar setup, but a factory TBI with 80lb. GM injectors @ 25psi) your pulse width would likely be quite low. Mine is around 0.9mS-1.0mS, DC (duty cycle) hovers around 2-3%. I've seen RBob say to disable ASync (INJ - ASync Transition PW - TBI Only field in TunerPro) by setting both fields to 0.00, though I don't fully understand this myself (I'm still learning too).

skerlock

Thank you...Looking at that what is this?

Scott

Cflick

About VE and fuel....

Short version : Higher VE causes the ECM to deliver more fuel.
If the VE is correct, then the calculated amount of fuel will produce a BLM at 128.
If there is not enough fuel ( running lean ) then the BLM goes UP to add fuel so as to correct for a LEAN condition, and vice versa. The VE is too low at that point.

Longer version :
VE is (V)olumetric (E)fficiency. How efficient is the engine at pumping air ?
If you have a 350 running at 2000 RPM, then the *theoretical* air flow at 100% VE is X CFM.
If the engine is only 50% efficient ( VE=50 ) then there is only 1/2 X air flowing, so you only need 1/2 the theoretical amount of fuel, to maintain the same AFR, because AFR is by weight, not volume.
Obviously, closing the throttle restricts air, lowering the VE. ( so does exhaust back pressure, valve timing, and such )
When you once get the VE table correct, so that it correctly indicates how much AIR ONLY is flowing through the engine at X RPM and Y MAP, then you know how much fuel to flow to achieve the desired AFR by weight. After that, the commanded AFR will match the actual AFR. If the VE table is low, telling the ECM that less air is flowing than is actually flowing, the ECM supplies as much fuel as should be required for the amount of air it *thinks* is flowing, but because the VE table is low, MORE air is actually flowing, so the engine is lean. The O2 sensor reports lean, and the INT responds by adding fuel. If the INT stays adding fuel for a long(er) time, the BLM goes up, until the O2 sensor reports the desired AFR is, in fact, coming out of the engine.
You ( or VE Learn ) then adjusts the VE table upwards to hopefully indicate the correct VE, and hence the correct air flow, which the ECM can then use to calculate the correct fuel.
Once the VE table *is* correct, the ECM merely looks up the VE value, multiplies the calculated fuel by the VE, and the AFR by weight is also correct.
When you manage to achieve that correct VE, as indicated by BLM corrections being very small, you LEAVE IT ALONE and address other things that affect special conditions, like PE, DE, and such.
The BLM will never actually stay solid 128, and that's why it exists ! If it's raining, then some of the oxygen in the air is replaced by water, so the engine appears rich, and the BLM corrects. If it's a cold day, the air is denser, so the same CFM contains more oxygen, and the engine appears lean, so the BLM indicates the correction.

In your case, BLM 140, you are lean and need more fuel, not less !!
Probably, your VE table is low, so the engine thinks less air is flowing than actually is.
The high BLM tells you that the ECM is adding fuel above what the VE says it should be, because the O2 sensor is telling the ECM that the final result is LEAN.
When the O2 says A-OK, then the BLM freezes at that number, and the AFR is correct, though the VE is still wrong.
When VE is correct, the BLM will freeze at 128, until something changes, like the weather, going up a mountain, anything that affects the AIR flow through the engine.

Remember, VE reflects AIR flowing through the engine.
If you know how much air actually is flowing ( an accurate VE, hard ) and you know what the desired AFR is supposed to be ( easy ) then you can calculate the amount of on-time to send to the injectors, assuming all of the injector data, fuel pressure, and such is accurate. ( moderately hard )
You make your best guess, and then check it with the O2 sensor in the exhaust flow, closing the loop.

If you're running a blower, have the perfect cam at the perfect RPM, then inertia of the weight of air, exhaust vacuum, blower pressure, and such, can cause air to compress in the cylinder before the compression stroke. Since AFR is by weight, and not volume, a VE greater than 100% is possible.
Most of us are not likely to see real VE above 100%.

Hope this helps....

Doober

Oh, I forgot to mention the 383 passed emissions I can manage to get it to idle smoothly, but the WB reads around 12-13:1, I'd like to get it a little leaner if possible. Does anyone have any suggestions? If I lower VE anymore in the idle range it starts hunting again & does the stall saver thing. I tried completely zeroing high/low idle compensation, but that made no difference.

The VFPR is a variable fuel pressure regulator. It allows you to run a lower fuel pressure at idle, which allows the computer to more finely tune the fuel delivery. Have you verified your fuel pressure is at 22lbs.? I was thinking a high BLM meant it was adding fuel, but wasn't sure enough to post on it.

skerlock

Great explanation. I am running a K&N filter In the 360 degree Open air cleaner. and 3" pipe with a flow master 40 no cat exhaust. So I need to let the VE learn run longer and smooth it out as the values climb. Raise the lower values that do not learn.

Scott

P.S. The higher the BLM the leaner the engine because it is telling the engine to push more fuel.

skerlock

I was running the Same injectors and setup at 13.5 Psi and had a very nice tune going. Staying close to the 128 BLM. I changed to More Injector pressure 22 psi and now im lean even though I did not use the same tune. I started from the same EBL Bin file EBL_F_2011.
Closest thing I could find as a Base starting point. Ill keep plugging away...

Scott