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DuramaxPowered
October 28th, 2009, 02:20 PM
Is anyone having luck with controlling the fuel rail pressure? I'd like to be able to bring pressure up sooner to help with my bigger nozzles, but this table isn't correct to begin with. At 720RPM idle speed I see 30 MPA when up to operating temp, not even close to the 60MPA shown for the area I'm idling at. Cold start never gets that high either.

tinman22
October 28th, 2009, 04:00 PM
there are multiplier tables at work between the ECT, IAT , and baro tables. dont know what software version your running but my desktop has been updated to the DSP beta and my fuel pressure column is way different than what you have posted. my lap top is not updated yet but its not here to look at. i'm guessing that the ultiplier tables are takeing affect and why your seeing less than what the base tables are showing

DuramaxPowered
October 30th, 2009, 04:20 AM
The rail pressure table are not correct. I just loaded a tune into my truck with 30MPA additional across the board, on every rail pressure table. Check rail pressure at idle before and after loading the tune and it is the exact same, 30MPA.........:help::grin:

tinman22
October 30th, 2009, 04:59 AM
hmmm interesting

fire0021
October 30th, 2009, 05:21 AM
The rail pressure table are not correct. I just loaded a tune into my truck with 30MPA additional across the board, on every rail pressure table. Check rail pressure at idle before and after loading the tune and it is the exact same, 30MPA.........:help::grin:

what version are you running Down load the latest Dsp release that went out last night the lmm tables are fixed

DuramaxPowered
October 30th, 2009, 05:58 AM
what version are you running Down load the latest Dsp release that went out last night the lmm tables are fixedI'll try them, I updated my desktop to the LMM DSP calz, but not my laptop......

DuramaxPowered
October 30th, 2009, 06:04 AM
It was brought up on another forum by Dustin from Diesel Addiction that there may be a table similar to {B1012} for an LLY that we're missing.......

killerbee
October 30th, 2009, 06:13 AM
The rpm axis is off. Use the LBZ

0 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400 2600 2800 3000 3200 3400 3600 3800 4000

DuramaxPowered
October 30th, 2009, 06:41 AM
No, it's not the labels. I added 30MPA to the entire table, on every rail pressure table, flashed the tune and the rail pressure didn't change at all.

killerbee
October 30th, 2009, 06:45 AM
Didn't mean to be premature. I will be following this as well. I was given that guidance and was passing it along.

If you are correct, this is a big problem for me.

Ross, can you squeak this in, buddy, pal, prettty please. ??

killerbee
October 30th, 2009, 06:47 AM
Is it idle mode (only) that is messed up for you? Or all ops.

DuramaxPowered
October 30th, 2009, 07:05 AM
cruising on the highway it's off also.......Rail pressure should be 17000 according to the tune, but desired and actual from scan tool is showing 11500-12000psi. Seems to be off everywhere.

killerbee
October 30th, 2009, 07:19 AM
cruising on the highway it's off also.......Rail pressure should be 17000 according to the tune, but desired and actual from scan tool is showing 11500-12000psi. Seems to be off everywhere.

even with the suggested rpm axis changes? IOW changing the axis (in your mind) should reveal a long hand way of seeing a valid number. (if I am correct)

It is just hard to know if I am communicating my thought.

DuramaxPowered
October 30th, 2009, 07:42 AM
I'll look at the table using LBZ labeling.............Idling definately has a different table that it references.

DuramaxPowered
October 30th, 2009, 07:45 AM
There are 20 columns in an LBZ rail pressure table and 23 in the LMM......

killerbee
October 30th, 2009, 08:16 AM
There are 20 columns in an LBZ rail pressure table and 23 in the LMM......


yuh, excel is your friend. Hope you are good with interpolation programming.

killerbee
October 30th, 2009, 08:18 AM
or

the new calz files may have addressed this. Have you swapped them out yet?

killerbee
October 30th, 2009, 08:34 AM
I just tried it. The new CALZ does not address this from what I can see.

GMPX
October 30th, 2009, 02:34 PM
I don't have any development stuff on my laptop so I can't really double check anything, but maybe also try changing B1059, your fuel pressure maybe getting limited by too little desired flow from that table.

killerbee
November 1st, 2009, 04:46 AM
B1056 is a problem also. It is defined as an ECT pressure correction, but I don't see an ECT element in the table, or an ECT multiplier.

killerbee
November 1st, 2009, 09:04 AM
There is something wrong with the main tables, but I am not sure I am putting my finger on it.

killerbee
November 21st, 2009, 11:57 PM
bump. There is no way to build a tune if rail pressure cannot be predicted.

http://forum.efilive.com/attachment.php?attachmentid=6541&d=1256782545

killerbee
January 18th, 2010, 03:48 PM
Buehler...Buehler...