Civic Hatchback L4-1493cc 1.5L SOHC (D15B1) TBI (1990)
EGR Control Solenoid Valve: Description and Operation
Fig. 13 Control Box Components And Vacuum Connections (CALIFORNIA A/T)
The EGR Control Solenoid Valve, mounted inside of the control box, is used to vary the amount of EGR valve lift. The ECU contains memories for
ideal EGR valve lifts for varying operating conditions. The EGR valve lift sensor detects the amount of EGR valve lift and sends the information to the
ECU. The ECU then compares it with the ideal EGR valve lift which is determined by signals sent from the other sensors. If there is any difference
between the two, the ECU cuts current to the EGR Control Solenoid Valve to reduce vacuum applied to the EGR valve.