Contents Wiring diagrams Section: Auxiliary Emission Control Systems All sections

Engine Emission Control System: Other Ford Escape III

EGR System

The EGR system returns a small amount of exhaust gas into the intake manifold. This reduces the overall combustion temperature. Cooler combustion temperatures provide a significant reduction of the Nitrogen Oxides (NOx) in the exhaust emissions.

The engine incorporates a stepper motor-controlled EGR valve which receives its signal from the PCM. Engine coolant is used to cool the EGR valve. The EGR valve and stepper motor are serviced as an assembly.

The amount of recirculated exhaust gas depends on

  1. engine rpm.
  2. intake manifold vacuum.
  3. exhaust backpressure.
  4. engine coolant temperature.
  5. throttle position.

PCV System

The PCV system uses intake manifold vacuum to ventilate blow-by vapors from the crankcase and return the vapors to the intake manifold for combustion. The PCV valve varies the amount of blow-by vapors returned to the intake manifold based on available engine vacuum. The PCV valve is serviced as part of the crankcase vent oil separator.

REFER to the INTRODUCTION - GAS .

Exhaust Gas Recirculation (EGR) Valve - 2.5L

ItemSpecification
Motorcraft® Metal Surface Prep ZC-31-A

MATERIAL SPECIFICATIONS

Crankcase Vent Oil Separator - 1.6L GTDI

ItemSpecification
Motorcraft® SAE 5W-20 Premium Synthetic Blend Motor Oil (US); Motorcraft® SAE 5W-20 Super Premium Motor Oil (Canada) XO-5W20-QSP (US); CXO-5W20-LSP12 (Canada)WSS-M2C945-A

MATERIAL SPECIFICATIONS