The 1998 Nissan Maxima uses the exhaust-gas recirculation system to route excess exhaust gas back into the engine to reduce emissions. The EGR valve works in conjunction with the electronic control module and canister control solenoid valve. If the ECM detects certain conditions, such as low engine coolant temperature, high-speed engine operation and engine-idling conditions, among other things, the EGR system routes exhaust gas back into the intake system so as to reduce emissions.
Disconnect the EGR valve’s vacuum lines by pulling them off the EGR valve. If the vacuum lines have clamps, loosen the clamps with a screwdriver. The EGR valve is on the rear of the intake manifold.
Loosen the exhaust inlet pipe, using the appropriate wrench. Remove the EGR valve retaining nuts, then lift the EGR valve off the manifold, taking care not to damage the gasket. Though you can reuse the gasket, it is recommended that you replace it.
Spray carburetor cleaner on the gasket mating surfaces on the EGR valve and the intake mounting service. Wipe the surfaces with a rag. Spray the carburetor cleaner into the valve opening and shake it out to loosen the carbon buildup. Repeat until the carbon is out of the valve.
Line the gasket and the EGR valve up on the intake manifold-mounting surface. Insert the bolts and tighten them to 13 foot-pounds of torque. Reconnect the EGR vacuum lines and tighten exhaust inlet pipe using the appropriate wrench.
