Other than the exhaust parts like the catalytic converter and oxygen sensor, your vehicle is equipped with a lot more components that help keep emission levels safe. One example of this is an exhaust gas recirculation system, a system that allows a little amount of exhaust to flow to the intake manifold to dilute the mixture inside the cylinders, cooling it in order to promote a more efficient fuel burn. For the EGR to work, it needs a high-quality EGR vacuum solenoid. Why? The EGR system operates with the help of vacuum, but it only functions well at a certain engine RPM measurement, often at around 2,000 RPM. When it is operated at an RPM lower than the correct level, some engine problems may occur (i.e. stalling and rough running). The EGR vacuum solenoid works like a switch that turns the EGR on when the right operating conditions are already achieved. When operated, the part will open the vacuum port to allow the passage of a little amount of exhaust gas. Damage in the EGR vacuum solenoid can cause problems with the operation of the EGR system. When symptoms of failure occur, have the system inspected by a professional mechanic. If the damage is beyond repair, replace the part immediately. Find your needed EGR vacuum solenoid replacement at Car Stuff!