Engine Emission Control - 3.0l (4v) Lincoln Zephyr US

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

The engine emission control system consists of the

1. Positive crankcase ventilation (PCV) system.
2. Exhaust gas recirculation (EGR) system.

Positive Crankcase Ventilation (PCV) System

The PCV system

1. Uses intake manifold vacuum to ventilate blow-by fumes from the crankcase.
2. Returns the fumes to the intake manifold for combustion.

The PCV valve

1. Varies the amount of blow-by gases returned to the intake manifold based on available engine vacuum.
2. Prevents combustion gases backfiring into the crankcase.

The PCV system consists of the

1. Fresh air tube.
2. Cam cover fitting.
3. Crankcase ventilation tube.
4. Positive crankcase ventilation valve.

The PCV heater element

1. Heats the ventilating air and blow-by gases going to the intake manifold.

Exhaust Gas Recirculation (EGR) System

The exhaust gas recirculation (EGR) system

1. Returns a small amount of exhaust gas into the engine for recombustion.
2. Reduces the overall combustion temperature and provides a significant reduction of oxides of nitrogen (NOx).

The EGR valve

1. Is electronically controlled by the powertrain control module (PCM).
2. Is connected to the exhaust manifold by the EGR valve-to-exhaust manifold tube.
3. Controls recirculated exhaust gas flow to the intake manifold.
4. Monitors the flow of recirculated exhaust gases through the EGR valve-to-exhaust manifold tube.
5. Returns a signal to the PCM.

The amount of recirculated exhaust gas depends upon

1. Engine RPM.
2. Intake manifold vacuum.
3. Exhaust back pressure.
4. Engine coolant temperature.
5. Throttle position.

The vehicle emission control information (VECI) decal

1. Is located on the hood.
2. Lists the exhaust emission control system information.

Refer to the INTRODUCTION - GASOLINE article.

Scheme 1

1. For additional information, refer to the appropriate procedure.

Removal and Installation

1. Disconnect the exhaust gas recirculation (EGR) valve electrical connector.
2. Disconnect the EGR tube fitting from the EGR valve. To install, tighten to 40 Nm (30 lb-ft).
3. Remove the 2 bolts and the EGR valve. Discard the gasket. To install, tighten to 25 Nm (18 lb-ft).
4. Clean the mating surfaces of any residual gasket material.
5. To install, reverse the removal procedure.

Scheme 2

1. With the vehicle in NEUTRAL, position it on a hoist. For additional information, refer to «JACKING & LIFTING»(/lincoln/zephyr/us-2006-2006/remont/hoistjack/#jacking-lifting) .
2. If equipped, remove the 7 screws and the underbody cover.
3. Disconnect the exhaust gas recirculation (EGR) tube fitting from the EGR valve. To install, tighten to 40 Nm (30 lb-ft).
4. Disconnect the exhaust manifold-to-EGR valve tube fitting from the exhaust manifold. To install, tighten to 40 Nm (30 lb-ft).
5. Remove the exhaust manifold-to-EGR valve tube.
6. To install, reverse the removal procedure.

Scheme 3

1. Disconnect the positive crankcase ventilation PCV tube quick connect coupling from the PCV valve and position the tube aside. For additional information, refer to «FUEL SYSTEM-GENERAL INFORMATION»(/lincoln/zephyr/us-2006-2006/remont/fuel-system/#fuel-system-general-information) .
2. Disconnect the PCV valve electrical connector.
3. Rotate counterclockwise and remove the PCV valve from the valve cover. Discard the PCV valve. For installation, make sure the PCV valve electrical connector is pointing in the correct position to allow the wiring harness to be connected. Incorrect installation would require removal and replacement of the valve.
4. To install, reverse the removal procedure.

See also:
• JACKING & LIFTING
• FUEL SYSTEM-GENERAL INFORMATION