Camaro, Firebird, 1999 - 2002

Engine Control Module (ECM)


The Camaro & Firebird 5.7L V8 engines use a PCM. For 5.7L V8 applications, see Powertrain Control Module (PCM).

Removal & Installation

Engine control module (ECM) service should normally consist of either ECM replacement or electrically erasable programmable read only memory (EEPROM) programming. If the diagnostic procedures require ECM replacement, check the ECM first to see if the correct part is being used.

In order to prevent internal ECM damage, the ignition must be OFF when you disconnect or reconnect the power to the ECM. For example, disconnect the power when you work with the following components:

A battery cable
The ECM pigtail
The ECM fuse
The jumper cables

 When you diagnose or replace the ECM, remove any debris from the ECM connector surfaces before servicing the ECM module connector gaskets. Ensure that the gaskets are installed correctly. The gaskets prevent intrusion into the ECM. The replacement ECM MUST be programmed.

 It is necessary to record the remaining engine oil life. If the replacement module is not programmed with the remaining engine oil life, the engine oil life will default to 100%. If the replacement module is not programmed with the remaining engine oil life, the engine oil will need to be changed at 5000 km (3,000 mi) from the last engine oil change.

  1. Using a scan tool, retrieve the percentage of remaining engine oil. Record the remaining engine oil life.
  3. Remove the wheelhouse filler panel.
  5. Disconnect the ECM electrical harness connectors.
  7. Loosen but do not remove the ECM rear retaining fastener. Use the rear retaining fastener as an anchor for the outer bracket.
  9. Remove the front retaining fastener from the ECM.
  11. Reposition the ECM outer bracket.
  13. Remove the ECM from the bracket and the vehicle.

To install:

  1. Install the ECM to the ECM rear bracket.
  3. Position the ECM front bracket.
  5. Install the ECM front retaining fasteners. Tighten the ECM retaining fasteners to 2.0 Nm (17 inch lbs.).
  7. Connect the electrical connectors to the ECM. Tighten the ECM electrical connectors to 8 Nm (70 inch lbs.).
  9. Install the wheelhouse filler panel.
  11. If a replacement ECM is being installed, it must be reprogrammed.