Help with csp5 2800rpm fuel issue?

[superwagon]

I was hoping somebody might help me out. I have not been able to figure out why I keep loosing mm3 and duration but noticed it seems to be tied to 2800 rpm. I am attaching my csp5 tune file and two logs. CMB_0084 log is starting the pull in overdrive and it downshifts to 3rd unlocked and then locks up. If you watch commanded mm3 and duration drops once rpms hit 2800. The CMB_086 log I start the pull in tow haul locked in 3rd so the rpms dont jump above the 2800 and it seems to fuel much better until I reach that 2800 again?
The tune is csp5 on tune 3. I would appreciate any help or ideas on this!
Thanks!
Doug

[Alex S.]

i've founght with similar issues and still do on some tunes. I would gladdly take a look at the file, however Ive not updated my EFI live in awhile so I can't open your tune file. I have a similar higher rpm issue with the tune I've playing with in my truck now. Above 26-2800 rpm it starts pulling back CMD.Fuel. The tune calls for 150 but usually only hit mid-high 140's and it starts going down with rpm until the trans shifts and rpms drop and then it shoots back up and starts doing the same thing once the next gear gets into that rpm range. Every once in awhile it will go to 150mm3 and stay there as long as I hold the pedal down and be a nice flat line on the log, but I'm not sure why. I have all but the boost and density limiters set to 150mm3 and those are both at 150mm3 in higher rpms. If I get a chance to update EFI later today I'll look and see if I see anything, but I'm no pro either. It's hard to get information on this kinda stuff. I've had some help from Les and the guys at anarchy, which I'm grateful for, but even they were pretty general and vague in anwering questions. I have asked about this limiter issure previously and never got much input from anyone, perhaps you'll have better luck.

[superwagon]

I would appreciate another set of eyes. Came across another thread that mentioned MINJSTAT_F so I monitored and found it switching to 12 when I get to 2800 and fueling starts to go south. From what I gather this indicates a rpm limiter in effect? Not sure what other numbers mean? 7= no limiter, 15= altitude limiter, 12= rpm limiter. Difficult to find much info on this but I was able to remedy a major defuel I had that related to 15.

[30 RUM]

Superwagon,

Take the truck out and Log Engine Load (I wish it was in EDA). I have a feeling you will see the Load decrease as RPM increases past 2800. Once Load starts falling off so does fuel demand. On my truck 07 5.9 manual, it would pull down to 75% load at 3400 Rpm. We do not have access to a load reference table with EFI Live.

[superwagon]

Thanks 30 Rum,

I will try to get a log with load monitored and see if it's doing the same as yours.

I have gotten a few other suggestions and a tune file to try but I haven't been able to get time to try anything since I posted this.
Thanks again!

[30 RUM]

No problem, with out looking at the tune yet, that is the first thing that comes to mind. When I get some time I will go through your tune and see if anything jumps out at me.

[kyle027]

Did this problem get resolved? Cause I'm having the same issue.

[superwagon]

I had to stop pushing my truck so hard until the transmission got built. I ran into some issues with my trans build and sent it out to be gone through again. When I get it back I plan on revisiting this.

[CapitalDiesel]

im having this issue to, noticed it when i logged my dyno run, mm^3 commanded just starts dropping off even though tps is at 100% and duration limiters are disabled. also happens right around 2800 in OD...subscribing.

[computerjlt]

i too am having the same issue as the OP....

advice i got was "tune around it" but it would be nice to hold commanded to redline (especially if its bumped up)

[superwagon]

I have got my built tranny back in but haven't retested as far as the defuel issue. I will try to retest tonight.

[kyle027]

I finally got mine to stop defueling I believe the limiter I was hitting ended up being the boost fuel limiter.

[Mitco39]

Guys, play special attention to your axis's. I fought with this last night before realizing how stupid I was for missing it. Look through your limiter tables and play close attention to the rpm column, you'll see what I saw if you do that.

[CapitalDiesel]

Guys, play special attention to your axis's. I fought with this last night before realizing how stupid I was for missing it. Look through your limiter tables and play close attention to the rpm column, you'll see what I saw if you do that.

Nope not my issue, I have gone through ALL limiter tables and have rpm axis up to 4200 and have no commanded fuel limiters under 145, I don't get it, my commanded fuel is getting pulled back and then when it shifts to the next gear it goes up and as rpm increases it drops again....

http://tapatalk.imageshack.com/v2/15/03/06/0623ab8ded05c8422f3ac227fe42aeaf.jpg

Green is duration, purple is commanded fuel, each humor where commanded fuel is highest is in the 2600-2900 rpm range

[CapitalDiesel]

All my limiters are disabled, all my limiter tables go to 4200rpm, and all my limiting tables are set at 145mm^3 above 2600, but I still see commanded fuel being pulled after 2600-2900rpm. any other thoughts?

[garrettg.bpd]

Boost pressure needs to be less then 50psi including atmospheric pressure. And fuel pressure need to be close to desired.

[garrettg.bpd]

If the pcm sees 50psi on the map sensor it thanks there a fault. If fuel pressure stays to low it will pull mm3

[CapitalDiesel]

Boost pressure needs to be less then 50psi including atmospheric pressure. And fuel pressure need to be close to desired.

Less than 50psi in my tuning? Cause my twins are not meant to be under 60psi at wot. Can you go into a little more detail?

Also the fuel pressure, I did put in a Duramax spring in my fuel return valve (12psi rated instead of 18psi) because I have a Duramax as a second pump. So I would decrease it in the table?


EDIT- I See I will alter my axis so that it will not go off the table, aka max my table to 70psj even though I don't think the sensor will read that high

[garrettg.bpd]

Rescale the boost sensor so it's max boost is 49.

[CapitalDiesel]

What will that do? My "fuel limiter, boost" table only goes to 32psi, wouldn't I want either the table to either go higher or the boost sensor to read only up to 31psi? Trying to understand this all, thanks

[garrettg.bpd]

If I remember correctly 50psi is 5 volts. If the pcm sees 5 volts it thanks there is a fault. All of your maps stop with less boost then your truck can produce. So where ever you boost exceeds the value in your tables the max value will be what use at the end of your run.

[garrettg.bpd]

If you would like pm, email or post your tune and log so I can review it in the a.m.

[CapitalDiesel]

Can I get your email

[garrettg.bpd]

[email protected]

[CapitalDiesel]

[email protected]

Sent

[Ghostman]

Bringing this back alive. I am having a similar issue. It slowly pulls command after each shift. I have all limiters turned off and re-scaled boost table. Scratching my head right now.

19445
19446

[garrettg.bpd]

What's your fuel pressure doing?

[Ghostman]

What's your fuel pressure doing?

Stays steady right at ~23k psi.

[tylerltr450]

Did you change your shifting for rpm and command?

[Ghostman]

Did you change your shifting for rpm and command?

Yes I did some. It's like it's keeping main duration under 2000 so it pulls command.

[garrettg.bpd]

Can you post your log file

[tylerltr450]

1945019450


You adjusted all of this?

[Ghostman]

Can you post your log file

Here are my last three

19451

19452

19453


1945019450




You adjusted all of this?


Yes I do have all those tables adjusted.

[garrettg.bpd]

It appears that your hitting a rpm limiter. I would say log with all the EDA pids. Post your new logs with all the pids and raise the rpm limiters to what you feel is safe for your engine.

[Dom_c13b]

19455

You need to adjust this table. Read each one carefully and adjust as you see fit. This is my current table. I shift at 3900 rpm and have no de-fueling issues. With some adjustments I've run my truck up over 5,000rpm and most of the adjustments need to be to this table. As long as you have all of the other limiters taken care of this should help you.

[Ghostman]

It appears that your hitting a rpm limiter. I would say log with all the EDA pids. Post your new logs with all the pids and raise the rpm limiters to what you feel is safe for your engine.

I will add all EDA and log again.


19455

You need to adjust this table. Read each one carefully and adjust as you see fit. This is my current table. I shift at 3900 rpm and have no de-fueling issues. With some adjustments I've run my truck up over 5,000rpm and most of the adjustments need to be to this table. As long as you have all of the other limiters taken care of this should help you.

Ok, well I thought I had those tables taken care of but maybe not. I'm just going to copy yours there and see what it does on next log.

Thanks for help guys. I will post back with results.

[Dom_c13b]

Yea let us know the out come. It took me a long time to finally figure out full fueling above 2800rpm, I feel like I searched and read every thread about it but never found much conclusive. A lot of people like to hold on to those secrets it seems.

[Ghostman]

Ok so i logged with all EDA parameters and changed my limiters to match the ones posted. It's definitely better but still not quite 100% there. I didn't get a chance to do a real good WOT pull either on this run but you can still see it taper off. I am getting over 2000us easily now especially in the lower gears. Here is a snap shot of log; my log file is slightly too big to attach. I also attached my tune.

Also, off-topic side note here, I adjust my main timing table up a bit and wow made a big difference in pep and power and much less smoke. I think I can even go a little more on my timing.

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19475

[Dom_c13b]

I can't open your tune file for some reason. Do you have a real old version of efilive? I'd like to check it out. I'm sure we can get it to fuel harder

[arinkuddy]

You need to adjust this limiter

19476

you might try setting this to minimum as well

19477

[arinkuddy]

opened fine for me

[Ghostman]

I can't open your tune file for some reason. Do you have a real old version of efilive? I'd like to check it out. I'm sure we can get it to fuel harder

I have the latest versions of EFI live. I'll load it again. 19478 Try this file. It is CSP5 file.


You need to adjust this limiter

19476

you might try setting this to minimum as well

19477

Ok I found the first table your talking about. What are the base table selections though? What does the 0, 1, 2, 3, 4 represent?

Ok the second limiter(B9904) I have disabled.

[Move'n Up]

Which Program are you running in the tune 1-5?

[Ghostman]

Tune #4 right now

Tune 1 is valet mode, Tune 2 is pretty much stock, Tune 3 is suppose to be a tow tune, but haven't messed with it so still stock, Tune 4 is current tuning I'm working on, tune 5 was an older tune I was running, did ok but didn't have enough timing.

[arinkuddy]

I have the latest versions of EFI live. I'll load it again. 19478 Try this file. It is CSP5 file.



Ok I found the first table your talking about. What are the base table selections though? What does the 0, 1, 2, 3, 4 represent?

Ok the second limiter(B9904) I have disabled.

0,1,2,3, and 4 are the air density selects... basically if you drive up a mountain and the baro drops its suppose to go to a different table(thats why you have 5 timing,pilot,pressure. etc ). The consensus is that it stays on 0 or base table all the time. I would put money that if you increased the 0 and maybe 1 column you would get your desired commanded fuel. you can see that at 2900 the limiter drops just like what you are seeing.

[Dom_c13b]

yea change that table to 145 across the board. I just updated to the latest pre release and was able to open it.

[arinkuddy]

you should post a log file after you change and test this for comparison

[Ghostman]

0,1,2,3, and 4 are the air density selects... basically if you drive up a mountain and the baro drops its suppose to go to a different table(thats why you have 5 timing,pilot,pressure. etc ). The consensus is that it stays on 0 or base table all the time. I would put money that if you increased the 0 and maybe 1 column you would get your desired commanded fuel. you can see that at 2900 the limiter drops just like what you are seeing.


yea change that table to 145 across the board. I just updated to the latest pre release and was able to open it.


you should post a log file after you change and test this for comparison

Ok thx guys. Will do that now and load a log.

[Ghostman]

BINGO!! We have a winner. Looks like table E2536 was the cure. Set column 0, and 1 to 145 all the way down and now full fuel. :anitoof:

19479

19480

Now I just need to figure out that dang 1-2-1-2 crap that happened. :shock:

19481

[Dom_c13b]

Glad it working out for you!

[GMPX]

I haven't followed along this thread but remember in the EDA data stream we have the air density table selection PID High and Low so you can see what tables the ECM will be running in.