A: Passages cast in intake manifold allow the EGR system to meter exhaust gases into the engine induction system. This is achieved by a valve that operates under vacuum or back pressure control in response to the engine load. Rough idling or stalling at idle, rough engine performance during light throttle application, and stalling during deceleration are some of the problems related to EGR systems in engines. Start the vehicle's engine then manually raise its EGR diaphragm to inspect through it. If the engine shuts off or its idle speed drops significantly, then the EGR valve is working properly. Examine all hoses connected to the valve for breaks, leaks, and kinks. Detach vacuum hose from the EGR valve and apply vacuum using a vacuum pump. The engine stumbling indicates that the vacuum diaphragm is working fine. Consult a reliable automotive repair company for proper checks on how effective your EGR control solenoid is operating on this vehicle. To replace any components, first separate the hose from the EGR valve before removing nuts or bolts that hold it onto either adapter or intake manifold. As you install another gasket lift out EGR valve from engine after it has been cleaned with dry cloth on mounting surfaces, put it in place with new EGR valve and proceed to connect hose for vacuum signal. Checking this linear EGR valve requires special electronic diagnostic equipment hence a qualified repair facility should do that examination. When replacing it, unplug electrical connector then take away mounting bolts followed by EGR valve which finally results in cleaning of mounting surface before installation of new gasket finished by tightening bolts firmly as well as connecting electrical connector into EGR valve itself.