Pages: [1]
Author Topic: Requested/Actual Boost not matching LDRXN?  (Read 690 times)
Swakefield
Jr. Member
**

Karma: +0/-2
Offline Offline

Posts: 34


« on: October 15, 2020, 05:10:40 PM »

Hey guys, so after not having my car for 2 weeks while i had a Single mass flywheel and rs4 clutch kit installed (b6 a4 1.8t), i ran the car on a mostly stock tune while i broke in the clutch. After breaking it in I redid my tune back to ~17PSI peak like I had before. I flashed it and I figured all was good (moron). 

My boost gauge has always been somewhat innacurate so i didnt question when it read low. But i ran a log now that I have a Surface 3 for logging and tuning(laptop battery crapped itself), and Ive found out it is actually running low. Even after re-flashing, the logs show that the ECU is only requesting about ~14.5PSI? Even though in LDRXN thts not correct. And it requests 14.5PSI for most of the RPM range which doesnt follow what LDRXN is set too? This all worked fine before and ran very well at the 17.5 I had it set for. Can someone tell me whats wrong?

Not triggering EGT protection. My buddy who uses nefmoto as well who is better than me isnt completely sure either.

Log/Bin/Xdf Attached!

Thanks in advance! please tell me its something simple and im a moron.

File is a 518AK me7.5

Logged

2002 Audi A4 B6 Avant 1.8t 5 Speed Quattro - Upgraded DV, Full Catless Exhaust, Chinese K04-015, Silicone TIP, Coilover Suspension
nyet
Administrator
Hero Member
*****

Karma: +490/-80
Offline Offline

Posts: 11038


WWW
« Reply #1 on: October 15, 2020, 05:18:44 PM »

This all worked fine before and ran very well at the 17.5 I had it set for.

You had what "set to 17.5"? LDRXN is not in PSI.

https://s4wiki.com/wiki/Tuning#Approximation

Log the rest of the req load variables.
« Last Edit: October 15, 2020, 05:22:10 PM by nyet » Logged

ME7.1 tuning guide (READ FIRST)
ECUx Plot
ME7Sum checksum checker/corrrector for ME7.x

Please do not ask me for tunes. I'm here to help people make their own.

Do not PM me technical questions! Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your experience.
Swakefield
Jr. Member
**

Karma: +0/-2
Offline Offline

Posts: 34


« Reply #2 on: October 15, 2020, 05:22:37 PM »

You had what "set to 17.5"? LDRXN is not in PSI.

https://s4wiki.com/wiki/Tuning#Approximation

In my xdf I have a second LDRXN labeled "LDRXN PSI" at the end with a conversion in it that gets it relatively close. Every single time ive ever used it before, its always been accurate to within ~.5psi.

I missed a few variables in the logger, had to re-set it up on the new tablet. Ill change it and re-log.
Logged

2002 Audi A4 B6 Avant 1.8t 5 Speed Quattro - Upgraded DV, Full Catless Exhaust, Chinese K04-015, Silicone TIP, Coilover Suspension
nyet
Administrator
Hero Member
*****

Karma: +490/-80
Offline Offline

Posts: 11038


WWW
« Reply #3 on: October 15, 2020, 05:23:56 PM »

In my xdf I have a second LDRXN labeled "LDRXN PSI" at the end with a conversion in it that gets it relatively close. Every single time ive ever used it before, its always been accurate to within ~.5psi

It isn't even close. There are a ton of other things that can affect it.

That approximation is a map I put in. I likely should not have, since people tend to think it means more than it is
Logged

ME7.1 tuning guide (READ FIRST)
ECUx Plot
ME7Sum checksum checker/corrrector for ME7.x

Please do not ask me for tunes. I'm here to help people make their own.

Do not PM me technical questions! Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your experience.
Swakefield
Jr. Member
**

Karma: +0/-2
Offline Offline

Posts: 34


« Reply #4 on: October 16, 2020, 06:36:57 AM »

Here is an updated log from this morning. I even tried an old bin from before I had my clutch done when it was hitting 17psi and it made no difference.
Logged

2002 Audi A4 B6 Avant 1.8t 5 Speed Quattro - Upgraded DV, Full Catless Exhaust, Chinese K04-015, Silicone TIP, Coilover Suspension
nyet
Administrator
Hero Member
*****

Karma: +490/-80
Offline Offline

Posts: 11038


WWW
« Reply #5 on: October 16, 2020, 12:14:57 PM »

rl_sol is low due being capped by rl_max (LDRXN is rlmx). you'll need to log the other torque limits. Please reread the wiki.

https://s4wiki.com/wiki/Tuning#Boost_.28rlsol.29_intervention_via_rlmax
Quote
However, there are many things which cause rlmax to not follow rlmx

Please log them.
Logged

ME7.1 tuning guide (READ FIRST)
ECUx Plot
ME7Sum checksum checker/corrrector for ME7.x

Please do not ask me for tunes. I'm here to help people make their own.

Do not PM me technical questions! Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your experience.
Swakefield
Jr. Member
**

Karma: +0/-2
Offline Offline

Posts: 34


« Reply #6 on: October 23, 2020, 06:19:42 AM »

rl_sol is low due being capped by rl_max (LDRXN is rlmx). you'll need to log the other torque limits. Please reread the wiki.

https://s4wiki.com/wiki/Tuning#Boost_.28rlsol.29_intervention_via_rlmax
Please log them.
Thank you for putting up with my lack of knowledge, you were right, i adjusted KFLDHBN(not at my computer so I cant confirm thats correct).  Now it follows KFLDHBN and I use ldrxn as a backup, set just higher than my highest curve in KFLDHBN (roughly).

Just to clarify, I know one axis is rpm, is the other coolant temp or IAT?( in reference to KFLDHBN.

Sent from my SM-N975U using Tapatalk

Logged

2002 Audi A4 B6 Avant 1.8t 5 Speed Quattro - Upgraded DV, Full Catless Exhaust, Chinese K04-015, Silicone TIP, Coilover Suspension
nyet
Administrator
Hero Member
*****

Karma: +490/-80
Offline Offline

Posts: 11038


WWW
« Reply #7 on: October 23, 2020, 11:28:27 AM »

Thank you for putting up with my lack of knowledge, you were right, i adjusted KFLDHBN(not at my computer so I cant confirm thats correct).  Now it follows KFLDHBN and I use ldrxn as a backup, set just higher than my highest curve in KFLDHBN (roughly).

Just to clarify, I know one axis is rpm, is the other coolant temp or IAT?( in reference to KFLDHBN.

Sent from my SM-N975U using Tapatalk



Please consult the FR. Considering this is a pressure ratio, see if you can guess which makes more sense, from a physics standpoint:
Logged

ME7.1 tuning guide (READ FIRST)
ECUx Plot
ME7Sum checksum checker/corrrector for ME7.x

Please do not ask me for tunes. I'm here to help people make their own.

Do not PM me technical questions! Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your experience.
Swakefield
Jr. Member
**

Karma: +0/-2
Offline Offline

Posts: 34


« Reply #8 on: October 23, 2020, 12:21:42 PM »

Please consult the FR. Considering this is a pressure ratio, see if you can guess which makes more sense, from a physics standpoint:
IAT makes more sense. My buddy said he thought it was coolant which didn't make sense to me.

Sent from my SM-N975U using Tapatalk

Logged

2002 Audi A4 B6 Avant 1.8t 5 Speed Quattro - Upgraded DV, Full Catless Exhaust, Chinese K04-015, Silicone TIP, Coilover Suspension
Pages: [1]
  Print  
 
Jump to:  

Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Page created in 0.018 seconds with 18 queries. (Pretty URLs adds 0s, 0q)