EGR valve replacement may be necessary if your vehicle has failed an emissions test. Exhaust gas recirculation is a technology developed over the past 20 to 30 years. The EGR valve is located on the engine intake manifold, and the top is distinctly saucer shaped. Check the schematic under the hood of the vehicle. There will be a vacuum line connecting the EGR valve to a solenoid. The EGR valve recirculates 5 to 15 percent of the engine exhaust back through the cylinders,displacing oxygen and lowering combustion temperatures. Less nitrous oxide is formed and released at the tailpipe. Other benefits include reductions in throttling loss, heat rejection, chemical dissociation, and specific heat ratio. Replacing your EGR valve is lengthy procedure that requires a few simple tools and plenty of confidence. Follow these tips to ensure success.
1. Save Money
Prolong the life of your EGR valve by spraying it with carburetor cleaner regularly. When it is time to replace the valve, shop online for replacement parts.
2. Find Socket and Crescent Wrenches
You will need a good set of wrenches to disconnect and reconnect all the hoses and pipes associated with the engine exhaust recirculation system. Find a deep well socket wrench with sockets of appropriate diameter. When putting the system back together, tighten nuts by hand first before finishing with the wrenches. This will help you keep the parts level and square, especially since you will work in tight spaces. Do not over torque any of the fasteners. Only tighten them 1/4-turn past snug.
3. Remove Brake Booster
Remove the vacuum hose connecting the EGR valve to the brake booster. It is a rubber grommet that will pop when you unseal it.
4. Unhook EGR Valve
Disconnect the vacuum line between the EGR valve and the solenoid by breaking the rubber grip from the steel nipple. Disconnect the exhaust pipe from the valve by loosening a nut with a wrench. Work carefully because the pipes may be corroded.
5. Remove Mounting Brackets
Use the socket wrench to loosen the nuts holding the EGR valve mounting bracket. You can now pull off the old EGR valve and install the new one.
6. Prep Mounting Gasket Surface
Use a razor blade to scrape the remnants of the old mounting gasket off the intake manifold. Work carefully so that you don't scratch the aluminum. Take the new gasket and thread the mounting bolts through the holes. This will help you to hold the new gasket in place while you are screwing the mounting bolts into the intake manifold. Finish tightening the bolts with a socket wrench.
7. Reconnect Tubes
Plug the vacuum line into the new EGR valve, then fit the exhaust pipe with the wrench. Plug the rubber grommet for brake booster hose back in. Finish tightening the mounting brackets if necessary.
8. Drive Vehicle
You have now completed the installation of the new EGR valve. Test drive the vehicle to verify that it works. If there are no other problems, the vehicle should easily pass the emissions test.