How do you change the egr valve on a 1994 mercury grand marquis?

Answer 1

Jack up the passengers side of the car, get a 1 1/16" wrench break loose the fitting to the manifold, hold a 24 mm wrench on the fitting to the manifold, loosen the flare nut on the tube. Then using a 10 mm socket, about 2 inches long, loosen the two nuts under the EGR valve, then take the both out, remove the vacuum hose to the top of the EGR valve, and the sensing line from the small tube. then completely remove the flare nut from the orifice fitting on the manifold. BE CAREFUL with the tube, do not bend it or break it, you may find PB blaster useful the night before on a cold engine loosen these fittings. Once the EGR valve is out, remove the orifice out of the manifold, remove the tube from the EGR valve, again be careful, mark the tube to EGR position before pulling this off, because the top fitting to EGR needs tightened before you put it back in, it will make the lower fitting difficult if you do not line it up right, dry fitting from under the car is helpful, mark it, and then tighten the top. Clean out the tube, be careful not to bend the little tube, either inside or outside the larger tube, it sticks out inside. Clean the orifice, clean the manifold face carefully not to score it, check for blockage there too. Apply antisieze to the orifice, put it back in the manifold, then apply antisieze to the bolts for the egr valve, and the flare nuts both ends. Apply some silicon to the egr valve face, just enough to hold the gasket in place, put the new gasket on, start the bolts two turns in the gasket, it will hold them in place, then start them in the manifold, then start the lower flare fitting to orifice, tighten the top bolts, and then the flare nut, connect the vacuum line, connect the sensing line. I just recently did this process, it works, if have other EGR issues, the valve is the easiest.

Answer 2

With the engine on idle, locate the PCV valve and use pliers to pinch the PCV hose that is located between the intake manifold and valve. Wait to hear the spring loaded valve click, and if you do not hear this, remove the valve but leave it connected to the intake manifold. Find the vacuum, and if you cannot, remove the valve from the hose and see if the engine stalls. You can find more instructions in an online manual.