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Title: Requested boost problem ME7.5 Post by: lawer on December 23, 2013, 04:59:37 PM Hi to all
I am facing a very strange problem with my car and a file that I did. The requested boost at top RPM is dropping suddenly too low I request 220% load and 100% torque at 220% I don't understand why at low-mid range I have normal boost request at 2350-2400mbar and suddenly in 5000RPM it drops to 1700mbar causing hard TP cuts I have also tested flat 215% LDRXN but I just got 2550mbar at low RPM boost request but at 5000 I had the same issue! I will appreciate anyone in advance level who will help me or advice me In the attachment you will find my current mod Regards, Lawer Title: Re: Requested boost problem ME7.5 Post by: oldcarguy85 on December 23, 2013, 05:20:04 PM What turbo is on the car?
Title: Re: Requested boost problem ME7.5 Post by: nyet on December 23, 2013, 07:30:29 PM Impossible to tell w/o logs.
Title: Re: Requested boost problem ME7.5 Post by: lawer on December 24, 2013, 08:02:44 AM We talk about stock turbo and st2 tune (intake + exhaust)
this log is done with flat 220% LDRXN see at high RPM what I am talking about Title: Re: Requested boost problem ME7.5 Post by: littco on December 24, 2013, 09:06:48 AM We talk about stock turbo and st2 tune (intake + exhaust) this log is done with flat 220% LDRXN see at high RPM what I am talking about Any stock turbo requesting 220load at 5000rpm is going into negative deviation and limp mode... Never in the month of Sundays is it going to hold/meet 220 load.. Title: Re: Requested boost problem ME7.5 Post by: nyet on December 24, 2013, 11:35:51 AM Please post raw .csvs, not xls files, which are useless for post processing
Title: Re: Requested boost problem ME7.5 Post by: lawer on December 25, 2013, 02:36:52 AM as you can see my mod file it is not flat 220% but dropping 160%!
as I said also I did a test with flat 220% but the requested boost at top RPM is not 2550 but 1700mbar This is my problem at 5000RPM I have spec load 191.7 spec corr load 208 req boost 1800mbar Title: Re: Requested boost problem ME7.5 Post by: littco on December 25, 2013, 04:26:15 PM as you can see my mod file it is not flat 220% but dropping 160%! as I said also I did a test with flat 220% but the requested boost at top RPM is not 2550 but 1700mbar This is my problem at 5000RPM I have spec load 191.7 spec corr load 208 req boost 1800mbar Still don't know why your trying to run 191load or more on a turbo that'll never make it! Title: Re: Requested boost problem ME7.5 Post by: nyet on December 25, 2013, 05:47:52 PM And I still dont see a csv
Title: Re: Requested boost problem ME7.5 Post by: ddillenger on December 25, 2013, 06:00:10 PM DMVDUB said he's got this.
Title: Re: Requested boost problem ME7.5 Post by: lawer on December 30, 2013, 01:49:48 PM here is the .csv that you asked for
You can see the problem starting from 4500RPM where my boost drops but requested load and corrected requested load is high as I have set it via software whatever I do to load request, the boost request drops to 0.5-0.6bar from 4500-limiter This is really odd to me Title: Re: Requested boost problem ME7.5 Post by: nyet on December 30, 2013, 04:05:57 PM Any stock turbo requesting 220load at 5000rpm is going into negative deviation and limp mode... Never in the month of Sundays is it going to hold/meet 220 load.. This. You're going to limp because you can't ever reach that requested load/boost. Also, not sure what is up with your csv... is that an old version of VCDS? The headers are useless. They all say load and abs. pressure with no indication of what is desired etc. Title: Re: Requested boost problem ME7.5 Post by: ddillenger on December 30, 2013, 04:37:12 PM Interesting tag in that file.
Title: Re: Requested boost problem ME7.5 Post by: brs on August 13, 2018, 12:12:38 PM Hi all
i know this topic very old but any found a solution ?After 5700rpm request boost drops speedly. Log is here Thanks in advance Title: Re: Requested boost problem ME7.5 Post by: brs on August 14, 2018, 11:33:16 AM any idea or a hint ?
Title: Re: Requested boost problem ME7.5 Post by: jimmcgee5 on August 14, 2018, 12:58:36 PM look at your injector duty cycle
Title: Re: Requested boost problem ME7.5 Post by: brs on August 14, 2018, 02:14:09 PM look at your injector duty cycle Thanksi will try a different big injector.i wonder Will it cause rlsol_w drop? Title: Re: Requested boost problem ME7.5 Post by: nyet on August 14, 2018, 04:31:16 PM It only means it would be safer to request more boost. If you want to request more load, request more load.
Title: Re: Requested boost problem ME7.5 Post by: nyet on August 14, 2018, 08:09:43 PM If you want to debug KFMIRL you'll need to log mifa/milsol/misopl/mimax
Quote The stock KFMIOP map is at most around 80%, so increasing the last column of KFMIRL is not sufficient, unless you increase the last column of KFMIOP. Done properly, mimax should be safely high enough to never limit torque request, such that it is higher than mrfa from KFPED. Quote If there is requested load intervention, you will see mifa following mimax instead of mrfa, and thus a different rlsol result from KFMIRL than expected. https://s4wiki.com/wiki/Tuning#Tuning_KFMIOP_and_KFMIZUFIL Title: Re: Requested boost problem ME7.5 Post by: brs on August 31, 2018, 08:59:18 AM Hi all
There is requested load intervention and i couldn't understand what cause. New log attached,what am I miss out ? thanks in advance Title: Re: Requested boost problem ME7.5 Post by: nyet on August 31, 2018, 09:20:13 AM Look at injector dc and lambda control.
You're out of fuel, req less boost up top. Title: Re: Requested boost problem ME7.5 Post by: brs on August 31, 2018, 10:06:51 AM Look at injector dc and lambda control. You're out of fuel, req less boost up top. Thanks,they are s3 injectors with K04 turbo.Out of fuel is it a little strange at this boost? :-\ Probably fuel pump died I will check my fuel system. |