FixVault

Mixture Control (Duty) Solenoid Functional Check

  1. Disconnect O2 sensor and idle (vacuum) switch. With ignition on and engine off, check for repeated clicks from solenoid.
  2. If solenoid clicks, it passes functional test. If solenoid does not click, check solenoid connector for voltage using a test light. If voltage is not present, repair wiring problem. If voltage is present and solenoid does not click, replace duty solenoid.