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killerbee
May 19th, 2009, 03:24 AM
ok, I am confused. B0720 is the fuel pulse table. But it doesn't makes sense. In the LMM, compared to LBZ and LLY, this table has values that are entirely too large. Logs do not follow this table either.

This shows 55 mpa, 800 us, and 25mm^3. Not a valid pulse chart value.

Has anyone made sense of this?

camcojb
May 19th, 2009, 03:36 AM
My logs show the same. The only numbers that seem to line up are the full mpa and mm3 areas of the map, bottom right hand corner, in other words full throttle stuff.

Jody

killerbee
May 19th, 2009, 03:43 AM
The LMM table values just don't make sense for a stock table. If I am the first to post this discrepancy, it needs a close look, because this is the basic stuff.

All other model pulse tables make sense, this one is way out there.

Or I am missing something, and am about to be embarrassed.

abkimble
May 19th, 2009, 09:35 AM
LMM's show total pw then remove that of pilot and multipliers. Looks right to me. Without looking at the rest of the tune that is.

killerbee
May 19th, 2009, 09:50 AM
That doesn't make sense either. The log shows 800 us main and 312 us pilot. 1100 total. The total on the table is 1800 after interpolation.

what multipliers?

abkimble
May 19th, 2009, 03:40 PM
That doesn't make sense either. The log shows 800 us main and 312 us pilot. 1100 total. The total on the table is 1800 after interpolation.

what multipliers?

I get roughly 1882 ( edited * didn't read picture close enough at first * ) after all the math from just what you have posted. Post the tune so we can investigate further.

killerbee
May 19th, 2009, 03:47 PM
any stock LMM tune.

so i guess I am not getting it. What math?

abkimble
May 19th, 2009, 04:51 PM
So post the stock tune you are reporting.

As far as the math, all the pilots have to be considered. If this is a stock tune and a log of the stock tune..... Then this math would follow and you get exactly 1811.45pw. All this table says is, it takes an 1811.45 pw to get 25.9mm3 fuel at 55mpa All other injection times on and off for each of the injections have to be considered. If say post injection is removed that pw command will not change it will only be added to a different injection pw unless some limiter is set. And so on. Post the tune for further investigation.

camcojb
May 19th, 2009, 05:07 PM
So post the stock tune you are reporting.

As far as the math, all the pilots have to be considered. If this is a stock tune and a log of the stock tune..... Then this math would follow and you get exactly 1891pw. All this table says is, it takes an 1891 pw to get 25mm3 fuel at 55mpa All other injection times on and off for each of the injections have to be considered. If say post injection is removed that pw command will not change it will only be added to a different injection pw unless some limiter is set. And so on. Post the tune for further investigation.

I have the same question. Table B0720 for the LMM's is described as main pulse only, no pilots like the LBZ's. On mine there is only pilot 1 at a cruise, say 40-50 mph, no pilot 2 or 3, no post injections. Even if you add the main and pilot 1 it isn't close to what the table shows it should be for the fuel pressure and mm3.

What "math" are you using?

Jody

abkimble
May 19th, 2009, 05:16 PM
I have the same question. Table B0720 for the LMM's is described as main pulse only, no pilots like the LBZ's. On mine there is only pilot 1 at a cruise, say 40-50 mph, no pilot 2 or 3, no post injections. Even if you add the main and pilot 1 it isn't close to what the table shows it should be for the fuel pressure and mm3.

What "math" are you using?

Jody

Ok so post your tune also with a log.

GMPX
May 19th, 2009, 05:18 PM
On the LMM they went to the 6 pulse tables for each injection event (well, why not!).
So you have the Main Pulse length, Pilot 1 pulse length etc.
The Main pulse table {B0720} is still used for the main pulse time regardless of the Pilot / Post injection status. The difference in the LMM is the Pilot / Post tables have their own Pulse table unlike the LBZ which used {B0720} for all injection event pulse widths.

Is there anywhere in your logs where the numbers do line up?

abkimble
May 19th, 2009, 05:19 PM
On the LMM they went to the 6 pulse tables for each injection event (well, why not!).
So you have the Main Pulse length, Pilot 1 pulse length etc.
The Main pulse table {B0720} is still used for the main pulse time regardless of the Pilot / Post injection status. The difference in the LMM is the Pilot / Post tables have their own Pulse table unlike the LBZ which used {B0720} for all injection event pulse widths.

Is there anywhere in your logs where the numbers do line up?

One post says at wot. Which makes since due to having all but one injection. My thoughts exactly on wanting the tune as well to look at. Looking at the log and pw, unless the actual frp is not 55mpa, all injections come from this one table. Even a stock lly pw for 25mm3 is only around 900 with the same pressure. How does crank angle injector on time compare to the log?

camcojb
May 19th, 2009, 05:32 PM
On the LMM they went to the 6 pulse tables for each injection event (well, why not!).
So you have the Main Pulse length, Pilot 1 pulse length etc.
The Main pulse table {B0720} is still used for the main pulse time regardless of the Pilot / Post injection status. The difference in the LMM is the Pilot / Post tables have their own Pulse table unlike the LBZ which used {B0720} for all injection event pulse widths.

Is there anywhere in your logs where the numbers do line up?

wot................................. :) Otherwise, no, not anywhere I can see. I log pilot 1 through 3, and have logged post injection also (never on), and I only have #1 on at cruise plus the main US, and the two add up to much less than the number in the main injection table. However, when I open the scan tool and the tune, it highlights the cell, and it's never the cell that it should be according to the log. In other words, at a 60 mph cruise I'm at 24 mm3 and 66 mpa, which in the tune would be a 1531 US, yet my main is 639, pilot 1 is 298, and pilot 2, 3, and post injection 1 and 2 are off.

The cell that is highlighted is 20 mm3 and 190 mpa, which has a number of 790. Not sure what that means.

Jody

abkimble
May 19th, 2009, 05:35 PM
wot................................. :) Otherwise, no, not anywhere I can see. I log pilot 1 through 3, and have logged post injection also (never on), and I only have #1 on at cruise plus the main US, and the two add up to much less than the number in the main injection table. However, when I open the scan tool and the tune, it highlights the cell, and it's never the cell that it should be according to the log. In other words, at a 60 mph cruise I'm at 24 mm3 and 66 mpa, which in the tune would be a 1531 US, yet my main is 639, pilot 1 is 298, and pilot 2, 3, and post injection 1 and 2 are off.

The cell that is highlighted is 20 mm3 and 190 mpa, which has a number of 790. Not sure what that means.

Jody


It's not going to highlight the exact cell, this would require highlighting 4 cells to get to the number you post as 24mm3 and 66mpa. The only way one cell could be highlighted would be to have a commanded or actual of say 20mm3 and 60mpa.

camcojb
May 19th, 2009, 05:36 PM
Ok so post your tune also with a log.

cannot do that, it's a custom tune from a tuner, and although modded by me I cannot post the info. I'm just trying to find out how you come up with your numbers. It makes sense if you add up the main US, and all pilots and post injections to come up with the total in the main map, but in my case (and Killerbees it seems) they do not even come close to adding up.

I appreciate you trying to help, but unless you're doing something different than simply adding all the above it doesn't work on mine.


Jody

camcojb
May 19th, 2009, 05:37 PM
It's not going to highlight the exact cell, this would require highlighting 4 cells to get to the number you post as 24mm3 and 66mpa.

but why is it highlighting 190 mpa at a cruise, when that's obviously incorrect? And what 4 cells? I only have the main and pilot 1 active, nothing else. Maybe they show off but really are on, I dunno.............

Jody

camcojb
May 19th, 2009, 05:56 PM
after looking some more, if you add pilot 2 and pilot 3 to the mix, the numbers get pretty close. Thing is, both those pilots show off in the scan. Is it possible they're not really off, or that possibly the computer thinks they're on so that's why the main US is off?

Under what conditions do the #2 and #3 pilots become active? I don't see any controls for those, other than turning them off in the fuel pressure max pulses allowed table, but nothing that says when they're used.

I thought post injection was for the dpf.

abkimble
May 19th, 2009, 06:07 PM
but why is it highlighting 190 mpa at a cruise, when that's obviously incorrect? And what 4 cells? I only have the main and pilot 1 active, nothing else. Maybe they show off but really are on, I dunno.............

Jody

I hear you on the cruise range highlite..... I just look at the data lol...

As far as the four cells I mention, if say you want 159mpa pressure, you'd have to subtract the two cells at axis of pressure and then divide by ten then add back that number 9 times at the 150mpa cell number. Then say a quantity of 94mm3 of fuel then you'd have to do the same for the two cells that influence the mm3 axis. Then these two numbers would have be subtracted from one another and so on....

abkimble
May 19th, 2009, 06:11 PM
after looking some more, if you add pilot 2 and pilot 3 to the mix, the numbers get pretty close. Thing is, both those pilots show off in the scan. Is it possible they're not really off, or that possibly the computer thinks they're on so that's why the main US is off?

Under what conditions do the #2 and #3 pilots become active? I don't see any controls for those, other than turning them off in the fuel pressure max pulses allowed table, but nothing that says when they're used.

I thought post injection was for the dpf.


Oh no, they are off but as you say they are still being considered. Yes they have so many different tables but these tables are getting closer to reflecting actual times of 6 cycles in way less than 180 crank angle degrees.


So, Main is in-fact main but only when all other injection cycles are off.

abkimble
May 19th, 2009, 06:19 PM
Is PID FRP_C the only process for actual fuel rail pressure? If so, is it calculated or measured?

killerbee
May 20th, 2009, 12:07 AM
I have the same question. Table B0720 for the LMM's is described as main pulse only, no pilots like the LBZ's.


exactly my point also. The description of the table does not sync with this "math" explanation. I think we need help here.

abkimble
May 20th, 2009, 04:21 AM
exactly my point also. The description of the table does not sync with this "math" explanation. I think we need help here.


The " math " explanation as read above finds the pw for specific pressure/quantity. The rest is pretty easy...:doh2:

In a stock calibration there is never a time when main would be commanded alone at 55mpa and 25mm3. Look at the pilots to see that.

Let's see what the help you ask for comes up with.

camcojb
May 20th, 2009, 09:27 AM
In other words, at a 60 mph cruise I'm at 24 mm3 and 66 mpa, which in the tune would be a 1531 US, yet my main is 639, pilot 1 is 298, and pilot 2, 3, and post injection 1 and 2 are off.


Jody


The " math " explanation as read above finds the pw for specific pressure/quantity. The rest is pretty easy...:doh2:

In a stock calibration there is never a time when main would be commanded alone at 55mpa and 25mm3. Look at the pilots to see that.

Let's see what the help you ask for comes up with.

I'm going to try one more time, just because I'm stubborn.............. :grin: My above example is correct if pilot 2 and 3 are active, along with #1. Main US 639, 298 pilot 1, 299 pilot 2, and 299 pilot 3 = 1535. Box says 1531, plenty close enough.

Here's my problem with this though; according to the scan tool pilot 1 is the only one active. 2 and 3 are off during a cruise at 60 mph, never come on. Pilot 1 matches B9101 which is the pulse amount when pilot 2 is NOT going to come on, so that makes sense as #2 is not on. So in this example, if only the main and pilot 1 are on, why do they not add up to 1531? And can someone tell me when and why pilot 2 and 3 are used? I cannot find a single instance where pilot 2 and 3 are on with my truck. I see the tables in the tune, but no idea what makes them active.

You mentioned before that if the scan tool said the pilots were off, then they're off. So how do those two numbers add up to being correct? Or do I have to divide by 10, and multiply by 9, and .................. :hihi:

Jody

GMPX
May 20th, 2009, 10:26 AM
Not really running on all cylinders at the moment, I'll try to compile up a reply soon.

abkimble
May 20th, 2009, 10:48 AM
Not really running on all cylinders at the moment, I'll try to compile up a reply soon.

Sounds good to me.

abkimble
May 20th, 2009, 10:50 AM
Or do I have to divide by 10, and multiply by 9, and .................. :hihi:

Jody


Sure man, what ever gets you through the day.:hihi:

rcr1978
May 20th, 2009, 11:56 PM
I'm going to try one more time, just because I'm stubborn.............. :grin: My above example is correct if pilot 2 and 3 are active, along with #1. Main US 639, 298 pilot 1, 299 pilot 2, and 299 pilot 3 = 1535. Box says 1531, plenty close enough.

Here's my problem with this though; according to the scan tool pilot 1 is the only one active. 2 and 3 are off during a cruise at 60 mph, never come on. Pilot 1 matches B9101 which is the pulse amount when pilot 2 is NOT going to come on, so that makes sense as #2 is not on. So in this example, if only the main and pilot 1 are on, why do they not add up to 1531? And can someone tell me when and why pilot 2 and 3 are used? I cannot find a single instance where pilot 2 and 3 are on with my truck. I see the tables in the tune, but no idea what makes them active.

You mentioned before that if the scan tool said the pilots were off, then they're off. So how do those two numbers add up to being correct? Or do I have to divide by 10, and multiply by 9, and .................. :hihi:

Jody

I think I remember seeing them come on only during a regen, it's been a while since I have saw a regen :angel_innocent: but I have some logs of it happening a few times. I have set B1021 to 2 across the board so I only have the main and pilot1, I did'nt want any post injection's.

killerbee
May 21st, 2009, 12:05 AM
all this pilot talk is a mute point if

"Table B0720 for the LMM's is described as main pulse only"

The table description negates pilot pulse.

rcr1978
May 21st, 2009, 12:08 AM
Well I guess I lied pilot 3 I never saw active here is a small regen log if you want to see I logged all 3 pilot mm3's and both post mm3's.

abkimble
May 21st, 2009, 09:39 AM
all this pilot talk is a mute point if

"Table B0720 for the LMM's is described as main pulse only"

The table description negates pilot pulse.

When ONLY MAIN is active this table still holds water.

killerbee
October 18th, 2009, 09:30 AM
Not really running on all cylinders at the moment, I'll try to compile up a reply soon.

anything would help.