How Do I Replace an EGR Valve?

"How do I replace an EGR valve?" is a common question, as the EGR valve will usually carbon up after 100,000 miles.

In order to replace the EGR valve the first item on the agenda is to open the hood and locate the valve. The EGR valve is always located on the intake manifold. In appearance it resembles a small flying saucer on a pedestal. Although its purpose remains the same, the method of activation and control varies widely. 

Once you locate the EGR, clear anything out of the way that may interfere with the removal of the bolts securing the EGR to the intake manifold. Remove the vacuum line from the EGR. In the case of electronically operated units, remove the electrical connector. Foreign vehicles such as Honda have multiple vacuum lines to modulate the EGR. It is essential to replace these lines in the exact same location because they step the EGR to different degrees of opening. Mark these lines before removing them.

There is a large metal pipe attached to the EGR, which is the exhaust source. Soak the large nut down with rust penetrant and give it a few minutes to soak in. They tend to rust due to the heat. Use an adjustable wrench or a standard wrench of appropriate size to loosen the nut and remove the pipe from the EGR.

Use a 15mm wrench or socket, if it will fit, to remove the two bolts securing the EGR to the intake manifold. When removing the EGR make sure to save the aluminum-looking gasket or replace it if a new EGR is to be used.

If the EGR is to be cleaned or replaced be sure to clean the cavity in the intake manifold, which tends to carbon over, causing the caking problem with the EGR.

If the vehicle is a Ford product, it uses a BPFE valve to operate the EGR. This is a 3-inch square box on the firewall with two fat hoses on the bottom and one hose to the EGR. This is a back-pressure feedback type of system where it senses the differential pressure in the exhaust system, thereby adjusting the EGR opening and the timing of the opening. The two large hoses run from the exhaust system to the valve and have always posed a problem with clogging up due to the moisture in the system. Pull the two fat hoses off and bend them and shake the white powder out. Use a thin small screwdriver if necessary to promote the removal of this blockage. The EGR will not function if this is not accomplished. Replace the valve in reverse order of removal.