2000 Sunbird L4-121 2.0L VIN B 2-bbl (1984)
Engine Control Module: Technical Service Bulletins
Electronic Control Module - Service
Number 84-6 (Gasoline)-20
Date 2/84
Subject:
ELECTRONIC CONTROL MODULE SERVICE ON 2.0L (V.I.N. Code P) ENGINE - 1984 2000
The 1984 2000 uses a new type of Electronic Control Module. This ECM uses a PROM and a device called a CALPAC. The purpose of the CALPAC is
to allow fuel delivery in the event of PROM or ECM malfunction. The CALPAC has an access door in the ECM, and removal and replacement
procedures are the same as with the PROM..
Anytime an ECM replacement is required on the 1984 2000, both the PROM and CALPAC must be removed from the replaced ECM and installed into
the replacement ECM. If the CALPAC is left out, the engine will crank but will not run.
