Pages: [1] 2
Author Topic: 17964 - P1556 Charge pressure control; negative deviation. HELP please  (Read 9278 times)
maxXAM
Jr. Member
**

Karma: +0/-6
Offline Offline

Posts: 33



17964 - P1556  Charge pressure control; negative deviation. HELP please
« Last Edit: February 04, 2023, 04:23:26 PM by maxXAM » Logged
_nameless
Hero Member
*****

Karma: +342/-466
Offline Offline

Posts: 2802



« Reply #1 on: February 04, 2023, 07:21:27 PM »

17964 - P1556  Charge pressure control; negative deviation. HELP please
With zero relevant info...
Logged

Giving your mom a tuneup
nyet
Administrator
Hero Member
*****

Karma: +607/-168
Offline Offline

Posts: 12270


WWW
« Reply #2 on: February 04, 2023, 11:13:17 PM »

overboost.

https://s4wiki.com/wiki/Tuning#Negative_deviation_(overboost)
« Last Edit: February 04, 2023, 11:38:27 PM by nyet » Logged

ME7.1 tuning guide
ECUx Plot
ME7Sum checksum
Trim heatmap tool

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 ex
maxXAM
Jr. Member
**

Karma: +0/-6
Offline Offline

Posts: 33


« Reply #3 on: February 05, 2023, 02:46:17 PM »

i had this issue about week now with no fault codes stored on ecu and my boost guage won't pass 5 psi with no check light on,a friend of mine told me to get hard on my s4 get it under load its will throw codes i take my s4 for spin on highway i hit the gas on 3th gear full throttle suddenly check engine turned on when get to my home pluged in vagcom scanned for cods i found this code 17964 - P1556  Charge pressure control; negative deviation
Logged
nyet
Administrator
Hero Member
*****

Karma: +607/-168
Offline Offline

Posts: 12270


WWW
« Reply #4 on: February 05, 2023, 02:47:40 PM »

n75, wg lines, wg.
Logged

ME7.1 tuning guide
ECUx Plot
ME7Sum checksum
Trim heatmap tool

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 ex
maxXAM
Jr. Member
**

Karma: +0/-6
Offline Offline

Posts: 33


« Reply #5 on: February 05, 2023, 03:13:02 PM »

n75, wg lines, wg.
so this code means over boosting or under boost if over boosting this drive me to start checking  boost control starting from  n75 to wastegates 
Logged
nyet
Administrator
Hero Member
*****

Karma: +607/-168
Offline Offline

Posts: 12270


WWW
« Reply #6 on: February 05, 2023, 06:33:24 PM »

overboost -> limp -> limited to 5psi
Logged

ME7.1 tuning guide
ECUx Plot
ME7Sum checksum
Trim heatmap tool

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 ex
maxXAM
Jr. Member
**

Karma: +0/-6
Offline Offline

Posts: 33


« Reply #7 on: February 06, 2023, 03:12:24 PM »

Good news i fixed it
now my s4 hits 20psi again 
The check valve that connected between the intake manifold and evap valve was connected backwards
Logged
prj
Hero Member
*****

Karma: +1072/-481
Offline Offline

Posts: 6035


« Reply #8 on: February 07, 2023, 05:12:58 AM »

Everyone loves some boost in their fuel tank.
Logged

PM's will not be answered, so don't even try.
Log your car properly - WinOLS database - Tools/patches
nyet
Administrator
Hero Member
*****

Karma: +607/-168
Offline Offline

Posts: 12270


WWW
« Reply #9 on: February 07, 2023, 11:18:13 AM »

Everyone loves some boost in their fuel tank.

I'm trying to figure out how this led to neg deviation though
Logged

ME7.1 tuning guide
ECUx Plot
ME7Sum checksum
Trim heatmap tool

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 ex
prj
Hero Member
*****

Karma: +1072/-481
Offline Offline

Posts: 6035


« Reply #10 on: February 07, 2023, 11:26:09 AM »

I'm trying to figure out how this led to neg deviation though
If it was 10 years ago when I had the 2.7T hoses memorized in my head, I'd tell ya.
Logged

PM's will not be answered, so don't even try.
Log your car properly - WinOLS database - Tools/patches
maxXAM
Jr. Member
**

Karma: +0/-6
Offline Offline

Posts: 33


« Reply #11 on: February 07, 2023, 11:50:42 AM »

I'm trying to figure out how this led to neg deviation though
Grin Grin that's me, now i know why i smell gas on my s4 capin
Logged
phila_dot
Hero Member
*****

Karma: +173/-11
Offline Offline

Posts: 1709


« Reply #12 on: February 07, 2023, 06:37:10 PM »

I'm trying to figure out how this led to neg deviation though

P1556 is LDRA.

lde > EDLDRP and lditv_w >= TVLDMX for TDLDRA
Logged
nyet
Administrator
Hero Member
*****

Karma: +607/-168
Offline Offline

Posts: 12270


WWW
« Reply #13 on: February 07, 2023, 09:19:23 PM »

P1556 is LDRA.

lde > EDLDRP and lditv_w >= TVLDMX for TDLDRA

Yep, that's overboost... but why did the checkvalve error produce overboost?
Logged

ME7.1 tuning guide
ECUx Plot
ME7Sum checksum
Trim heatmap tool

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 ex
phila_dot
Hero Member
*****

Karma: +173/-11
Offline Offline

Posts: 1709


« Reply #14 on: February 08, 2023, 03:49:19 PM »

lde > EDLDRP

Actual boost is at least EDLDRP less than target

lditv_w >= TVLDMX

Max DC is unable to correct the error
Logged
Pages: [1] 2
  Print  
 
Jump to:  

Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Page created in 0.022 seconds with 17 queries. (Pretty URLs adds 0s, 0q)