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Diagnosis and Testing|Removal and Installation > < Engine Emission Control

C-MAX 2003.75 (06.2003-)

Engine Emission Control - 2.0L Duratorq-TDCi (DW) Diesel - Engine Emission Control— C-MAX 2003.75 (06/2003-)
Diagnosis and Testing

General Equipment
Worldwide Diagnostic System (WDS) (418-F224)

Principles of Operation

Exhaust Gas Recirculation (EGR) system

To maintain the standards of low exhaust emission levels required of todays engines, the EGR system on this engine is fully electronically controlled.

The EGR valve is a proportional electric motor controlled directly by a duty-cycle signal from the powertrain control module (PCM). Integrated into the EGR valve is a valve position sensor. The signal from the EGR valve position sensor allows for the precise control of the timing and the quantity of exhaust gas to be recirculated. If the EGR valve becomes inoperative or fails to close completely, the PCM will raise a diagnostic trouble code (DTC) and the instrument cluster malfunction indicator lamp (MIL) will be illuminated. At the end of each drive cycle the PCM drives the EGR valve to the fully open and fully closed positions several times. This assists with cleaning the EGR valve.

If a new EGR valve is installed. The base setting (closed position) value must be configured to the PCM. This is initiated using WDS. If the base setting is not configured to the PCM, the setting from the previous EGR valve will be used and the control function of the EGR system will be incorrect.

The EGR system is fitted with an EGR cooler. The EGR cooler reduces the temperature of the exhaust gasses being returned to the intake system. By reducing the EGR temperature, the intake air charge density is not adversely affected, so maintaining the optimum fueling characteristics.

Positive Crankcase Ventilation (PCV) system

 
Item
Part Number
Description
1
-
PCV valve diaphragm
2
-
PCV valve

The PCV system is made up of an oil separator chamber connected to the crankcase by a hose. The oil separator chamber is an integral part of the engine intake manifold.

The crankcase pressure is controlled by a diaphragm operated PCV valve built into the oil separator. As the pressure in the oil separator reduces, the diaphragm valve closes against the force of the PCV valve spring, so closing the PCV valve. As the crankcase pressure rises, the PCV valve is pushed open assisted by the PCV valve spring. This allows the positive crankcase gasses to be scavenged by the air intake system.

Inspection and Verification

  1. Verify the customer concern.
  1. Visually inspect for obvious signs of mechanical or electrical damage.

Visual Inspection Chart

Mechanical Electrical
  • Exhaust gas recirculation (EGR) valve
  • EGR tube
  • EGR cooler
  • EGR tube clamp
  • Gasket
  • PCV hose
  • PCV oil separator
  • Electrical connector
  • Wiring harness
  1. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
  1. If the cause is not visually evident, verify the symptom and refer to the DTC Index Chart.
  1. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnosis.

Diagnostic Trouble Code (DTC) Index Chart

DTC Description Possible Source Action
P1412 MIL illuminated EGR valve REFER to Excessive exhaust black smoke in the Symptom Chart
P0404 MIL illuminated EGR valve REFER to Excessive exhaust black smoke in the Symptom Chart
P1335 Powertrain warning indicator illuminated EGR valve REFER to Excessive exhaust black smoke in the Symptom Chart

Symptom Chart

Symptom Chart

Symptom Possible Sources Action
Excessive exhaust black smoke
*
EGR valve.
*
Using the WDS, CHECK the PCM calibration. If necessary UPDATE the PCM calibration to the latest level. Using the WDS, TOOLBOX/POWERTRAIN SERVICE FUNCTIONS/COMPONENT OR PARAMETER RESET/EGR RE-CALIBRATION, RESET the EGR valve. Carry out a road test, if the concern persists GO to Pinpoint Test A.
Excessive crankcase pressure
*
Blocked or damaged PCV hose(s).
*
Blocked PCV oil separator.
*
GO to Pinpoint Test B.
*
Worn or damaged engine components.
*
REFER to: Engine (303-01F Engine - 2.0L Duratorq-TDCi (DW) Diesel, Diagnosis and Testing).

Pinpoint Tests

PINPOINT TEST A : EXCESSIVE EXHAUST BLACK SMOKE
TEST CONDITIONS DETAILS/RESULTS/ACTIONS
A1: CHECK THE EXHAUST GAS RECIRCULATION VALVE POSITION
NOTE:
NOTE:Allow the engine to idle for a minimum of four minutes before carrying out the system checks using the WDS.
NOTE:
NOTE:After the engine is switched off, the EGR valve will attempt the cleaning cycle up to a maximum of 18 times. If 18 cycles are seen during the test the EGR valve is suspect and should be changed.
1
Ignition switch in position III.
2
Using the WDS, DATALOGGER, set the parameters DPFEGR, RPM, EGRDC#.
3
Set DATALOGGER to RECORD.
4
Ignition switch in position 0.

Does the DPFEGR 0 to 5 volt parameter change from a minimum approximate value of 0.9 volts to a maximum approximate value of 4.2 volts for a total of 6 cycles?
Yes
GO to A2.
No
RECORD the DTCs and DATALOGGER freeze frame data. INSTALL a new EGR valve.
REFER to: Exhaust Gas Recirculation (EGR) Valve (303-08C, Removal and Installation).
TEST the system for normal operation.
A2: CHECK THE EXHAUST GAS RECIRCULATION VALVE FOR DAMAGE
1
Remove the EGR valve.
REFER to: Exhaust Gas Recirculation (EGR) Valve (303-08D Engine Emission Control - 2.0L Duratorq-TDCi (DW) Diesel, Removal and Installation).
2
INSPECT the EGR valve and valve seat for damage or excessive carbon build up. REMOVE the plastic cover on the EGR valve and check the EGR valve cam actuator for free movement.

Is the EGR valve undamaged and in the closed position and the EGR valve cam actuator free to move?
Yes
To continue diagnostics,
REFER to: Fuel Charging and Controls (303-04E Fuel Charging and Controls - 2.0L Duratorq-TDCi (DW) Diesel, Diagnosis and Testing).
No
INSTALL a new EGR valve.
REFER to: Exhaust Gas Recirculation (EGR) Valve (303-08E Engine Emission Control - 1.6L (Z6), Removal and Installation).
TEST the system for normal operation.

PINPOINT TEST B : EXCESSIVE CRANKCASE PRESSURE
TEST CONDITIONS DETAILS/RESULTS/ACTIONS
B1: CHECK THE PCV HOSE FOR BLOCKAGE

1
Remove the PCV hose.
2
Inspect the PCV hose for blockage.

Is the PCV hose free from blockage?
Yes
GO to B2.
No
CLEAN or INSTALL a new PCV hose as necessary. TEST the system for normal operation.
B2: CHECK THE PCV VALVE FOR DAMAGE

1
Inspect the PCV valve for damage or blockage.

Is the PCV valve spring undamaged and the PCV valve free from blockage?
Yes
TEST the system for normal operation. If the concern persists,
REFER to: Engine (303-01F Engine - 2.0L Duratorq-TDCi (DW) Diesel, Diagnosis and Testing).
No
CLEAN the PCV oil separator and PCV valve assembly or INSTALL a new intake manifold as necessary.
REFER to: Intake Manifold - VIN Plate Emission Level Code: K (303-01F Engine - 2.0L Duratorq-TDCi (DW) Diesel, In-vehicle Repair) /
Intake Manifold - VIN Plate Emission Level Code: S (303-01F Engine - 2.0L Duratorq-TDCi (DW) Diesel, In-vehicle Repair).
TEST the system for normal operation.

Diagnosis and Testing|Removal and Installation > < Engine Emission Control