What to know about the EGR Control Solenoid:
Exhaust gas recirculation, or EGR, systems were developed to bring down engine emissions by reintroducing exhaust gas into the air/fuel mixture. This burns any remaining or partially burnt fuel in the exhaust and cools the combustion chamber, which creates fewer nitrous oxides.
EGR systems have changed significantly, shifting from vacuum solenoid to electrically controlled systems. Modern EGR valves employ a solenoid that controls the amount of exhaust that enters the intake process. Instead of being open and closed, the control solenoid ‘flutters’ rapidly, with the amount of open and closed times varying minutely with each flutter. When the engine temperature is cold, the EGR control solenoid enables little to no exhaust into the intake. While at wide open throttle, the solenoid is open nearly all the time.
When the EGR control solenoid doesn’t close during cold operation, the engine runs poorly or stalls. When the control solenoid doesn’t open the right way, engine pinging or knocking is readily heard. In any situation of EGR control solenoid malfunction, the Check Engine light will come on.
Facts to Note:
The EGR system works at high temperatures. Don’t touch the EGR valve or other parts until they have cooled off.
How to Fix:
The EGR control solenoid is confirmed that it needs to be changed. The engine trim cover is then removed for access.
The faulty EGR control solenoid is disconnected from it’s electrical connections and detached.
The new EGR control solenoid is fixed and the electrical connections reconnected.
The engine is started and the EGR control solenoid is tested for operation. The engine trim panel is then reinstalled.
The vehicle is road tested to make sure proper operation of the EGR control solenoid.
The EGR control solenoid does not need upkeep or servicing. If the EGR control solenoid is found to be faulty, it needs to be changed by one of your expert technicians. It is also a good idea to check the solenoid’s operation when the EGR valve is being changed.
Common symptoms indicating you may need to change the EGR Control Solenoid:
Engine runs rough or stalls at idle when cold
Check Engine light comes on
Engine pings or knocks when accelerating or under load
Importance of this service:
The engine will not run well with an improperly operating EGR control solenoid. Your vehicle could fail an emissions or smog test if the control solenoid isn’t working. Have it changed if it is deemed to be defective.