How to Remove the EGR Valve in a 1999 Ford F-250

The exhaust gas recirculation valve in your 1999 Ford F-250 Truck opens during steady cruise speed driving to allow exhaust gasses to flow back into the cylinder. This helps fuel mileage, as the recirculated gases take up space in the cylinder, allowing less of the air/fuel mixture to fill the cylinder. Due to the re-burning of the exhaust gasses, hydrocarbon and carbon monoxide emissions are lowered, as well. The operation of the EGR valve also provides a cooling effect during combustion, lowering combustion temperatures and oxides of nitrogen emissions. The average home mechanic can remove the EGR valve from the 199 F-250 in just a few minutes, using basic hand tools.

Instructions

1

Allow the engine to cool. Remove the three bolts located on the plastic engine cover, using a 10-mm socket and ratchet. Lift the cover up and out of the engine compartment.

2

Loosen the hose clamps that attach the air filter housing duct to the throttle body and the filter housing. Unlatch the filter housing clamp and unplug the mass air flow sensor connector. Lift the filter housing and duct from the engine compartment.

3

Locate the EGR valve on the driver's side of the throttle body adapter, between the throttle body and the firewall. Spray the fitting nuts on each end of the pipe that runs from the bottom of the EGR valve to the exhaust manifold with penetrating oil.

4

Remove the vacuum line from the top of the EGR valve. Remove the EGR pipe from the exhaust manifold, using an adjustable wrench or a 1 1/4-inch wrench. Spray the nuts with penetrating oil, as needed, to soften the rust so that the pipe can be removed.

5

Remove the two 13-mm nuts that attach the EGR valve to the intake manifold, using a 13-mm socket, extension, universal joint and ratchet. Slide the EGR valve and pipe off the intake manifold studs. Remove the EGR valve gasket. Remove the EGR pipe from the bottom of the EGR valve.

6

Clean the gasket surface on the manifold with a gasket scraper to remove the remains of the old gasket. Install the EGR pipe onto the new EGR valve loosely. Slide the new gasket over the studs on the intake manifold. Slide the new valve with the pipe onto the studs. Install the 13-mm nuts on the studs loosely.

7

Align the EGR pipe on the exhaust manifold fitting and start the nut onto the threads of the fitting by hand, to prevent cross-threading the fitting. Tighten the fittings securely. Tighten the EGR valve nuts securely. Reinstall the vacuum line onto the top of the valve.

8

Reinstall the air filter housing and engine cover. Clear any related trouble codes that may be stored in the on-board computer, using a scan tool or code reader.