The 1998 Ford Ranger came with three engine options; a 2.5-liter four-cylinder, a 3.0-liter V-6 and a 4.0-liter V-6. Although all three engines share very little in common in terms of design, each powerplant incorporates an exhaust gas recirculation valve, responsible for routing unspent hydrocarbons back into the combustion chamber. Over time, excessive amounts of carbon buildup may restrict the movement of the EGR's vacuum-operated diaphragm, and exhaust gas flow. Although cleaning a moderately mucked-up EGR valve with carburetor cleaner may help restore most of its functionality – damaged and out-of-spec EGR valves should be replaced.
Items you will need
- Combination wrench set
- Socket set
- Gasket scraper
- Shop rag
- Carburetor cleaner
- Torque wrench
- Crowfoot attachment
Allow the engine to completely cool and open the hood. On a 4.0-liter V-6 engine, the EGR valve is mounted above the driver-side cylinder head, near the front of the engine, while the EGR valve for the 3.0-liter V-6 engine is located above the passenger-side valve cover, near the front. For the 2.5-liter engine, the EGR valve is to the left of the valve cover, next to the throttle body.
Loosen the EGR tube fitting, using a wrench, and disconnect the tube from the EGR valve. Disconnect the small vacuum line connected to the top portion of the EGR valve, using your fingers. It may help to twist the base of the vacuum line connector to break the seal. If the vacuum line or rubber connector are damaged in any way, replace the vacuum line.
Remove the two hex-head bolts securing the EGR valve, using a socket, extension and ratchet. Remove the EGR valve. Plug the EGR port on the intake manifold with a shop rag, and remove any gasket material from the EGR's mating surface, using a gasket scraper if needed.
Spray the inside of the engine's EGR port with carburetor cleaner to dissolve and wash out excess carbon deposits. Dry the exposed areas of the EGR port, and clean the mating surface, using a shop rag.
Mount the replacement EGR valve to the intake manifold with a new gasket and the original bolts. Tighten the bolts to 15 foot-pounds, using a torque wrench, extension and socket.
Connect the EGR tube to the EGR valve. Tighten the fitting to between 25 and 35 foot-pounds, using a crowfoot attachment and torque wrench. Adjust the angle of the crowfoot to 90 degrees before tightening; this will minimize inaccuracy in the torque reading. Connect the vacuum line to the EGR valve.
- AllData 9.5; 1999 Ford Ranger; Powertrain Management; Emission Control Systems