Exhaust gas recirculation, function - GF14.20-P-3000P

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ENGINE 642 in MODEL 164.1 /8, 203.0 /2, 209.3 /4, 211.0 /2 /6, 219.3, 221.0 /1, 251.0 /1

ENGINE 642 in MODEL 461.3

ENGINE 642 in MODEL 463.3

Exhaust gas recirculation (EGR) is active at low load and speed ranges. Exhaust gas recirculation is carried out according to engine load and engine speed. To do this, the CDI control unit (N3/9) reads information from the following components:

Left hot film mass air flow sensor (B2/6) (except model 461)
Right hot film mass air flow sensor (B2/7) (except model 461)
Hot film mass air flow sensor (B2/5) (model 461)
Charge pressure sensor (B5/1)
Charge air temperature sensor (B17/8)
TWC [KAT] temperature sensor (B19)
Pressure sensor downstream of air filter (B28/5) (except model 463)
Pressure sensor downstream of air filter, right cylinder bank (B28/5) (Model 463)
Accelerator pedal sensor (B37)
Crankshaft Hall sensor (B70)

After evaluating the input signals, the CDI control unit uses the stored performance map to actuate the left exhaust gas recirculation positioner (Y27/9) (except model 461) or the exhaust gas recirculation positioner (Y27/9) (model 461) with a pulse width modulation (PWM) signal. The orifice area is enlarged, downsized or closed completely by the exhaust gas recirculation positioner, depending on actuation by the CDI control unit. More, less or no exhaust at all is fed back into the charge air manifold depending on the valve position.

Via EGR, the NO_X levels in the emissions are reduced. This takes place via the following 3 processes:

The oxygen (O₂ ) concentration is reduced in the combustion chamber
Reducing exhaust flow
Reduction of the combustion temperature by the higher heat collection propensity of the components (e.g. water (H₂ O) and carbon dioxide (CO₂ )), which are not involved in combustion, but influence the process

To increase effectiveness of the EGR, the exhaust gas is passed through the exhaust gas recirculation cooler.

The left exhaust gas recirculation positioner is integrated in the cooling circuit of the engine in the following models as protection against thermal loads:

Model 211.022 with OM 642.920 with code (494) USA version
Model 211.022/222 with OM 642.920 with code (498) Japan version
Model 211.024 with OM 642.920
Model 164.1/8 with OM 642.940 with code (494) USA version
Model 251.0/1 with OM 642.950 with code (494) USA version

Hot film mass air flow sensor, component description	B2/6, B2/7 Model 164.1/8, 203.0/2, 209.3/4, 211.0/2/6, 219.3, 221.0/1, 251.0/1, 463	GF07.07-P-6000P
	Model 461 B2/5	GF07.07-P-6000GX
Component description for the intake air temperature sensor	B2/6b1, B2/7b1 Model 164.1/8, 203.0/2, 209.3/4, 211.0/2/6, 219.3, 221.0/1, 251.0/1, 463	GF07.04-P-6070P
	Model 461 B2/5b1	GF07.04-P-6070GX
Component description for the boost pressure sensor	Model 164.1/8, 203.0/2, 209.3/4, 211.0/2/6, 219.3, 221.0/1, 251.0/1, 463 B5/1	GF07.04-P-6051P
	Model 461 B5/1	GF07.04-P-6051GX
Component description for the charge air temperature sensor	Model 164.8, 203.0/2, 209.3/4, 211.0/2/6, 219.3, 221.0/1, 251.0/1, 463 B17/8	GF07.04-P-6050P
	Model 461 B17/8	GF07.04-P-6050GX
Component description for the catalytic converter temperature sensor	Model 203, 209 B19	GF07.04-P-6110P
	Engine 642.920 in model 211.020/220/620, 219.322 Engine 642.921 in model 211.084/089/284/289 Engine 642.920 in model 211.022 except code (494) USA version Engine 642.920 in model 211.022/222 except code (498) Japan version B19	GF07.04-P-6110T
	Engine 642.920 in model 211.022 with code (494) USA version Engine 642.920 in model 211.024 B19	GF07.04-P-6110TU
	Engine 642.920 in model 211.022/222 with code (498) Japan version B19	GF07.04-P-6110TJ
	Model 164, 463 B19	GF07.04-P-6110GZ
	Model 251 B19	GF07.04-P-6110RT
	Model 461 B19	GF07.04-P-6110GX
Component description for the pressure sensor downstream of air filter	Model 164.1/8, 203.0/2, 209.3/4, 211.0/2/6, 219.3, 221.0/1, 251.0/1, 463 B28/5	GF07.04-P-6061P
	Model 461 B28/5	GF07.04-P-6061GX
Accelerator pedal sensor, component description	Model 203, 209, 211, 219 B37	GF30.20-P-2010P
	Model 164, 463 B37	GF30.20-P-2010GZ
	Model 221 B37	GF30.20-P-2010SX
	Model 251 B37	GF30.20-P-2010RT
Component description for the crankshaft Hall sensor	B70	GF07.04-P-6220P
Component description for CDI control unit	Model 203, 209 N3/9	GF07.16-P-6000P
	Model 211, 219 N3/9	GF07.16-P-6000T
	Model 164, 463 N3/9	GF07.16-P-6000GZ
	Model 221 N3/9	GF07.16-P-6000SX
	Model 251 N3/9	GF07.16-P-6000RT
	Model 461 N3/9	GF07.16-P-6000GX
Component description for vent line heater element	R39/1	GF09.00-P-4010P
Component description for the exhaust gas recirculation cooler		GF14.20-P-2020P
Component description for the exhaust gas recirculation positioner	Engine 642 in model 203.0/2, 209.3/4, 219.3, 221.0/1, 463.3 Engine 642.920 in model 211.020/220/620 Engine 642.921 in model 211.084/089/284/289 Engine 642 in model 164.1/8, 251.0/1, except code (494) USA version Engine 642.920 in model 211.022 except code (494) USA version Engine 642.920 in model 211.022/222 except code (498) Japan version Y27/9	GF14.20-P-4007P
	Engine 642.920 in model 211.022 with code (494) USA version Engine 642.920 in model 211.022/222 with code (498) Japan version Engine 642.920 in model 211.024 Engine 642 in model 164.1/8, 251.0/1, with code (494) USA version Engine 642 in model 461.3 Y27/9	GF14.20-P-4007TU
Throttle valve actuator, component description	Model 164.1/8, 203.0/2, 209.3/4, 211.0/2/6, 219.3, 221.0/1, 251.0/1, 463 M16/6	GF30.20-P-2020P
	Model 461 M16/6	GF30.20-P-2020GX