Pages: [1]
Author Topic: Knock sensor logging, multiple voltages?  (Read 1395 times)
TeknoFi
Full Member
***

Karma: +1/-3
Offline Offline

Posts: 85


« on: July 31, 2022, 01:00:51 PM »

Hello,

i have a 1.8t ajq (audi tt) with two sensors. why do I get four different voltages and how should they be interpreted?

each sensor gives one wire to the ecu, so where are the extra voltages coming to the logs?

According the logs, cylinders 1+3 and 2+4 give voltage close to each other, and between groups are bigger voltage cap. If the pairs were 1+2 and 3+4, I would melt it into the difference between the sensors, but this is too weird for me. Could someone please explain please.
Logged
fknbrkn
Hero Member
*****

Karma: +186/-24
Offline Offline

Posts: 1466


mk4 1.8T AUM


« Reply #1 on: July 31, 2022, 02:23:37 PM »


Ecu obviously knows when eqch cylinder are firing, no matter how much sensors it has
In case of two sensors first logs 1-2 and the second 3-4 cyl. Just for accuracy
In general you dont need all of this voltages except to diagnose dead sensor/wiring
Logged
nyet
Administrator
Hero Member
*****

Karma: +608/-168
Online Online

Posts: 12276


WWW
« Reply #2 on: August 01, 2022, 05:02:53 PM »

voltages mean literally nothing. They are heavily processed by the ECU.
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
Pages: [1]
  Print  
 
Jump to:  

Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Page created in 0.017 seconds with 17 queries. (Pretty URLs adds 0s, 0q)