Reported Bugs

  • Status Researching
  • Percent Complete
    70%
  • Category 07K ME17.5 (2009+)
  • Assigned To
    Jason
  • Priority Medium
Attached to Project: Reported Bugs
Opened by Jason - 06.10.2025
Last edited by Jason - 09.04.2026

FS#6 - Deceleration detection failure

Description

Some ME17.5 ECUs (Automatic only) fails to detect when the engine enters a deceleration state/overrun

Symptoms

  • Fuel trims stay active, interpreting the fuel cut on decel as a lean condition
  • ECU does not opt for the minimal ignition advance, causing jerkiness between shifts and no crackles on affect vehicles
Admin
Jason commented on 09.04.2026 06:16

Fuel trim remaining active is related to FS#4, without the fuel cut or cylinder suppression, the ECU does not assume a deceleration state. It targets a spark efficiency factor of 0.1

Adjusting the delta at 0.1 will fix the ignition advance, but it does not address the fuel trims:

  • Need to find a different way to trigger the deceleration state and disable the fuel trim on deceleration. Otherwise, it will cause false positives, and a surge of support tickets

Loading...

Available keyboard shortcuts

Tasklist

Task Details

Task Editing