Troubleshooting a Subaru Legacy EGR

The Legacy is a mid-size vehicle designed and manufactured by Subaru. The Legacy is equipped with an exhaust gas recirculation (EGR) valve. The EGR directs exhaust gases into the intake manifold, where the exhaust is cooled before entering the combustion chamber. This process reduces emissions and prevents the vehicle from overheating. If your Legacy is running poorly, it is important to check the EGR and troubleshoot it properly to see if the valve is dirty or damaged.

  • Park the Legacy and allow the vehicle to cool for 30 minutes.

  • Open the hood and find the EGR. The valve is located on the back side of the intake manifold, on the right side. The valve is a mushroom-type looking component with a hose coming off of it and leads to the manifold.

  • Turn on the engine. Allow the vehicle to warm up for a couple minutes. Go to the front of the vehicle and watch the EGR.

  • Notice the plunger mechanism in the middle of the valve. The plunger should move up and down freely. If the plunger moves up and down at a slow pace, the EGR needs to be cleaned as carbon buildup is in the way. If the plunger does not move at all, the EGR is faulty and needs to be replaced.