EXHAUST GAS RECIRCULATION
TABLE OF CONTENTS
page
page
EXHAUST GAS RECIRCULATION
DESCRIPTION
. . . . . . . . . . . . . . . . . . . . . . . . . . 4
VALVE
DESCRIPTION
. . . . . . . . . . . . . . . . . . . . . . . . . . 5
OPERATION
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
REMOVAL
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
INSTALLATION
. . . . . . . . . . . . . . . . . . . . . . . . . . 6
VALVE COOLER
DESCRIPTION
. . . . . . . . . . . . . . . . . . . . . . . . . . 6
EXHAUST GAS RECIRCULA-
TION
DESCRIPTION
The EGR system can provide up to 35% exhaust
gas recirculation. The EGR operates during all
engine speed and load conditions. At wide open throt-
tle, it provides a 5% recirculation rate. The EGR
shuts down during high engine idle to avoid carbon
build up on the valve. The EGR also deactivates if
the EGR temperature is too high. The EGR also has
a self cleaning function that opens and closes twice
after the engine has been shut off to eliminate soot
deposits.
Apart from the charge air distribution manifold
and the mixing chamber, the intake manifold also
includes a finned EGR cooler. Coolant flows through
the cooler to reduce the temperature of the recircu-
lated gas after it was cooled by running through the
cylinder head. The management of this temperature
significantly reduces emissions (Fig. 1).
25 - 4
EXHAUST GAS RECIRCULATION
VA