NefMoto

General => General Discussion => Topic started by: Jugoo on June 05, 2018, 05:48:08 AM

Title: Me7.1 limp mode
Post by: Jugoo on June 05, 2018, 05:48:08 AM

Hi!

Does anyone here know all or the most common causes in S4 B5 stock C-Box for limp mode?

Bad maf reading?
- N75 duty cycle?
- - Actual vs ordered boost pressure not matching = boost leak
  - - EGT reading too high?
    - - what else....?
      - I thought that this forum is the Place to ask this question, because knowledge about me7.1 coding.

Title: Re: Me7.1 limp mode
Post by: adam- on June 05, 2018, 07:44:16 AM

Why does it matter? Read the code and know exactly.

Title: Re: Me7.1 limp mode
Post by: nyet on June 05, 2018, 08:55:15 AM

The most common cause is the one that tells you the problem.

Title: Re: Me7.1 limp mode
Post by: Jugoo on June 05, 2018, 10:27:37 AM

Quote from: adam- on June 05, 2018, 07:44:16 AM

Why does it matter? Read the code and know exactly.

I wouldnt be asking this if any DTCs would be left.
After WOT boost drops from 1bar to 0,5bar. No DTC even read limp mode and car running. C-box is not showing EGT values in vcds. Boost leak test is made.

This is why I ask this question.

Title: Re: Me7.1 limp mode
Post by: nyet on June 05, 2018, 10:28:29 AM

Provide logs.

Do not post VCDS logs. Use ME7Logger.

Title: Re: Me7.1 limp mode
Post by: Jugoo on June 10, 2018, 04:42:20 AM

Hey nyet, heres (https://drive.google.com/drive/folders/1YYRnlJs8Q8SOBRyR_H8CWqgbNnVKSq0Y) graphs from logs. I attach also the .csv files so if you could look at them also.

Thank you.

Title: Re: Me7.1 limp mode
Post by: nyet on June 10, 2018, 09:41:23 AM

Looks like positive deviation limp (underboost) and/or i-max trim limit reached.

Would have to log i-limit and associated trims to be sure.

Make sure you don't have a boost leak

Check LTFTs to make sure they're sane

Increase IMX