ECM Replacement
If the engine control module (ECM) is replaced, the following procedures must be performed:
- ECM Reprogramming-Refer to Service Programming System (SPS) .
- Idle Learn Procedure-Refer to the appropriate procedure:
- Idle Learn Procedure in Engine Controls 1.4L DOHC
- Idle Learn Procedure in Engine Controls 1.6L (L91)
- Idle Learn Procedure in Engine Controls 1.8L (L79)
- Idle Learn Procedure in Engine Controls 2.0L (L34 GMDAT)
- The crankshaft position (CKP) System Variation Learn Procedure- Refer to CKP System Variation Learn Procedure in Engine Controls 1.8L (L79) or CKP System Variation Learn Procedure in Engine Controls 2.0L (L34 GMDAT).
- Theft Deterrent-Refer to Programming Theft Deterrent System Components (Scan 100) or Programming Theft Deterrent System Components (Tech 2) in Theft Deterrent. The ECM will learn the incoming fuel continue password immediately upon receipt of a password message. Once a password message is received, and a password is learned, a learn procedure must be performed to change this password again. An ECM which has been previously installed in another vehicle will have learned the other vehicle's fuel continue password, and will require a learn procedure after programming to learn the current vehicle's password.