Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSCHEVROLET1984CAVALIER L4-121 2.0L VIN P TBIREPAIR AND DIAGNOSISPOWERTRAIN MANAGEMENTCOMPUTERS AND CONTROL SYSTEMSTECHNICAL SERVICE BULLETINSALL TECHNICAL SERVICE BULLETINSELECTRONIC CONTROL MODULE - SERVICE
1984 Chevrolet Cavalier L4-121 2.0L VIN P TBI
Electronic Control Module - Service
1984 Chevrolet Cavalier L4-121 2.0L VIN P TBISECTION Electronic Control Module - Service
Number: 84-59
Section: 6E (VIt)
Date: Feb., 1984
Subject ELECTRONIC CONTROL MODULE
SERVICE ON 2.0L CODE P ENGINE
Model and Year: 1984 CAVALIER
TO: ALL CHEVROLET DEALERS
CALPAC:
The 1984 Cavalier 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 Cavalier, 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.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.