Firenza L4-112 1.8L VIN 0 TBI (1982)
![background image](/oldsmobile/firenza/l4-112_1.8l_vin_0_tbi/Page-754001.png)
Vacuum Check Valve: Description and Operation
OPERATION
Solenoid--energized by the ECM during cold engine operation--blocks ported vacuum to the EGR valve.
-
When engine temperature is at or above the value programmed into the ECM, the module de-energizes the solenoid, which then directs ported
vacuum to the EGR valve, activating the EGR system.