Exhaust Gas Recirculation: Service and Repair

EGR VALVE CLEANING

1. Holding valve in hand, tap lightly on sides and end of valve with plastic mallet to remove exhaust deposits from valve seat. Do not put valve in vise.
2. Using wire wheel, buff deposits from mounting surface and around valve.
3. Depress valve diaphragm and check that valve seating area is clean. If not, repeat step 1.
4. Remove any deposits in valve outlet with screwdriver.
5. Blow out remaining dust and particles with compressed air.
6. Check valve operation by applying 8 inches Hg. If valve does not open completely, replace valve.

EXHAUST GAS PASSAGE CLEANING

1. Inspect EGR gas passage into intake manifold for deposits. Using hooked awl, remove deposits, taking care to minimize amount falling into intake manifold.
2. Remove loose deposits with shop vacuum.
3. Check EGR pipe for excessive deposits (more than 5 to 10% blockage of pipe). Tap lightly on sides of pipe to loosen deposits, then remove with compressed air. Reassemble pipe.