Crown Victoria, Grand Marquis, Town Car, 2006-2007

Exhaust Gas Recirculation System


Description & Operation

EGR System Module

The ESM is an integrated differential pressure feedback EGR system that functions in the same manner as a conventional differential pressure feedback EGR system. The various system components have been integrated into a single component called the ESM. The flange of the valve portion of the ESM bolts directly to the intake manifold with a metal gasket that forms the metering orifice. This arrangement increases system reliability, response time, and system precision. By relocating the EGR orifice from the exhaust to the intake side of the EGR valve, the downstream pressure signal measures manifold absolute pressure (MAP). This MAP signal is used for EGR correction and inferred barometric pressure (BARO) at key on. The system provides the powertrain control module (PCM) with a differential pressure feedback EGR signal, identical to a traditional differential pressure feedback EGR system.

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Fig. Exhaust Gas Recirculation (EGR) System Module (ESM)

Removal & Installation

EGR System Module

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Fig. EGR system components


  1. Intake manifold shield retaining bolt (2 required)
  3. Intake manifold shield
  5. Exhaust gas recirculation system module electrical connector
  7. EGR system module
  9. EGR system module gasket
  11. EGR vacuum connector
  13. EGR system module retaining bolt (2 required)
  15. EGR tube fitting
  17. EGR tube
  19. Disconnect the exhaust gas recirculation (EGR) system module electrical connector and vacuum connector.
  21. Remove the 2 bolts and the intake manifold shield. To install, tighten to 9 ft. lbs. (12 Nm).
  23. Disconnect the EGR tube fitting from the EGR system module. To install, tighten to 30 ft. lbs. (40 Nm).
  25. Remove the 2 bolts and the EGR system module.
  27. To install, tighten to 18 ft. lbs.(25 Nm).
  29. Remove the EGR system module gasket and discard.
    Do not use metal scrapers, wire brushes, power abrasive discs or other abrasive means to clean the sealing surfaces. These tools cause scratches and gouges that make leak paths. Use a plastic scraping tool to remove all traces of the EGR system module gasket. If there is no residual gasket material present, metal surface cleaner may be used to clean and prepare the surfaces for assembly.

  31. Clean the mating surfaces of any residual gasket material.
  33. To install, reverse the removal procedure.
  35. Install a new EGR system module gasket with the side that has the raised circle facing the intake manifold.

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    Fig. EGR ESM gasket installation



EGR System Module

EGR ESM Pin Testing

For reference values, refer to PCM testing-PCM reference voltage chart

This pinpoint test is intended to diagnose the following:

ESM (9Y456)
Orifice tube assembly (9D477)
Differential pressure feedback exhaust gas recirculation (EGR) sensor pressure hoses
Vacuum lines
Harness circuits: VREF, DPFE, SIGRTN, EVR, VPWR and VREF

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