2882, 2883 Fuel Trim Adaptations

From Bavarian Technic

Jump to: navigation, search

Contents

This topic applies to

  • Chassis types E46, E83, E85, and E60, model years 2003+, and
  • Are equipped with the M54 engine, and
  • Use the MS45 or MS45.1 engine control unit, and
  • Display fault codes 2882 and 2883

Overview

On BMWs that fit the description above, an illuminated check engine light frequently leads to a couple fault codes in the engine control unit: 2882 and 2883. These faults indicate an air/fuel ratio that is too lean.

If you encounter these fault codes

  1. Check the additive and multiplicative fuel trim mixture adaptations. Determine whether they are in or out of the specified range. Typically, anything greater than 0.03ms or 6-8%, respectively, is out of range.
  2. Perform an air-induction system diagnosis by visually inspecting the intake system for leaks. Then, using a smoke machine, apply smoke to the intake after the mass airflow sensor (MAF) and check for leaks.
  3. After repairs, first reset the ECM via commands and then test-drive the vehicle for at least 20 minutes. Monitor the adaptation values [OMS11]and be sure that the values are starting to move back within the specified range. Once the values are within the appropriate range, you can clear the fault memory of the engine control unit.

Components that typically cause the problem include

  • Intake throttle boot
  • PCV system and connections
  • Secondary air one-way valve
  • Intake manifold gaskets
  • Fuel Filter clogged
  • Fuel Pump failure (pressure to low)

Other causes might include

  • A faulty MAF. In this case, look for contradicting adaptation values. When the adaptations are at their maximum value (eg + 15%) and the engine performance is low,you can generate a fault by disconnecting the MAF. If the performance is gone back to normal you must replace the MAF.
  • An incorrect air filter element
  • A cracked or leaking vacuum line
Personal tools