S10/T10 Blazer 2WD L4-119 1.9L VIN A 2-BBL (1984)
Malfunction Indicator Lamp: Description and Operation
Closed Loop Fuel Control System
During normal engine operation, the dashboard mounted ``Check Engine'' lamp is normally off.
If a problem develops in the ``Closed Loop Fuel Control System'' while the engine is running, the ``Check Engine'' lamp will light and a trouble code
will be stored in the ECM. The light will remain lit as long as there is a problem and the engine is running. If the problem should clear up, the ``Check
Engine'' lamp will go out, but a trouble code will be stored in the ECM. If the ``Check Engine'' lamp is On or was On, refer to System Self-Diagnosis.