Emissions Control: Removal & Installation Dodge Durango III

REMOVAL

Scheme 4

The Evaporative System Integrity Monitor (ESIM) (3) is very similar to the NVLD. However, the design of the ESIM has been simplified and unlike the NVLD the ESIM does not require a solenoid. The ESIM mounts directly to the EVAP vapor canister, eliminating the need for a mounting bracket. The EVAP vapor canister is located in the left rear quarter panel behind the left rear wheelhouse splash shield.

Scheme 5

1. Disconnect and isolate the negative battery cable (2).
2. Remove the fuel tank filler cap.
3. Raise and support vehicle.
4. Remove left rear wheel and tire.
5. Remove the left rear wheelhouse splash shield. Refer to «SHIELD, SPLASH, WHEELHOUSE, REMOVAL»(ref-465921-S10952698702012042300000) . NOTE: When removing the fresh air hose, remove the hose at the fresh air filter first, this will eliminate the risk of breaking the nipple from the ESIM during removal.
6. Carefully remove the ESIM fresh air hose (1) at the fresh air filter.
7. Disconnect the electrical connector (2) at the ESIM.
8. Rotate the ESIM (3) counter-clockwise about 70 degrees and remove.
9. Disconnect the vapor purge line (4) quick-connect fitting from the EVAP canister.
10. Disconnect the fuel tank vapor line (5) quick-connect fitting from the EVAP canister. The vapor canister is mounted to a V-Slot bracket and does not require any fasteners.
11. Depress the retaining tab (1) at the back side of the vapor canister and with a lifting motion remove the vapor canister from the V-Slot (2) mounting bracket.

INSTALLATION

The vapor canister is mounted to a V-Slot bracket and does not require any fasteners.

1. Position the vapor canister to the V-Slot (2) mounting bracket and slide the canister downward into the V-Slot until the retaining tab (1) clicks/locks in place. NOTE: The vapor/vacuum lines must be firmly connected. Check the vapor/vacuum lines at the EVAP canister for damage or leaks. If a leak is present, a Diagnostic Trouble Code (DTC) may be set.
2. Connect the fuel tank vapor line (5) quick-connect fitting to the EVAP canister.
3. Connect the vapor purge line (4) quick-connect fitting to the EVAP canister.
4. Position the ESIM (3) to the EVAP canister and rotate clockwise about 70 degrees and lock in place.
5. Connect the electrical connector (2) at the ESIM.
6. Carefully install the ESIM fresh air hose (1) at the fresh air filter.
7. Install the left rear wheelhouse splash shield. Refer to «SHIELD, SPLASH, WHEELHOUSE, INSTALLATION»(ref-465921-S28556323522012042300000) .
8. Install left rear wheel and tire.
9. Lower the vehicle.
10. Connect the negative battery cable (2).
11. Install the fuel tank filler cap.
12. Start the engine and check for leaks.

If replacement of the 1/4 turn fuel tank filler tube cap is necessary, it must be replaced with an identical cap to be sure of correct system operation.

The EVAP canister purge solenoid (1) is located in the engine compartment attached to a bracket mounted on the left strut tower.

1. Disconnect the vapor/vacuum lines (1, 2) at the canister purge solenoid.
2. Disconnect the electrical connector (3) at the canister purge solenoid.
3. Depress the retaining tab (4), slide the canister purge solenoid forward and remove solenoid from the mounting bracket.

1. Slide the EVAP canister purge solenoid onto the mounting bracket until the locking tab (4) click/locks into position.
2. Connect the electrical connector (3) at the canister purge solenoid.
3. Connect the vacuum/vapor lines (2, 1) at the canister purge solenoid.

Scheme 6

The Evaporative System consists of the following components

1. Purge Solenoid (1)
2. Intake Manifold (2)
3. Fuel Tank (3)
4. ORVR Control Valve (4)
5. ESIM (5)
6. Vapor Canister (6)
7. Fresh Air Filter (7)
8. Gas Cap (8)
9. Throttle Body (9)

The ESIM (Evaporative System Integrity Monitor) is very similar to the NVLD. However, the design of the ESIM has been simplified and unlike the NVLD the ESIM does not require a solenoid. The ESIM mounts directly to the canister, eliminating the need for a mounting bracket. It is critical that the ESIM is mounted vertically. On vehicles where the canister is mounted on an angle, the ESIM requires an adaptor to maintain a vertical position. When the ESIM is installed vertically, the electrical connector is in the 3 o'clock position.

Scheme 7

The ESIM consists of the following components

1. ESIM Housing (1)
2. Diaphragm (2)
3. Switch (3)
4. Cover (4)
5. Small Check Valve (5)
6. Large Check Valve (6)

There is one large weight and one small weight check valve in the ESIM assembly. A seal is attached at the end of each weighted check valve. The large weight check valve seals for pressure. The small weight check valve seals for vacuum. The weighted check valves are contained within the ESIM housing.

The ESIM (Evaporative System Integrity Monitor), while physically different than the NVLD system, performs the same basic function as the NVLD does - controlling evaporative emissions. The ESIM has been simplified because the solenoid used on the NVLD is not used on the ESIM.

Scheme 8

The ESIM consists of housing, two check valves (1, 4) (sometimes referred to as weights), a diaphragm (3), a switch and a cover.

During refueling, pressure is built up in the evaporative system. When pressure reaches approximately.5 inches of water, the large check valve (1) unseats and pressure vents to the fresh air filter.

Conversely, when the system cools, and the resulting vacuum lifts the small check valve from its seat and allows fresh air to enter the system through the fresh air inlet (2) and relieves the vacuum condition. When a calibrated amount of vacuum is achieved in the evaporative system, the diaphragm is pulled inward, pushing on the spring and closing the contacts.

The ESIM conducts test on the evaporative system as follows: An engine off, non-intrusive test for small leaks and an engine running, intrusive test for medium/large leaks.

The ESIM weights seal the evaporative system during engine off conditions. If the evaporative system is sealed, it will be pulled into a vacuum, either due to the cool down from operating temperature or diurnal ambient temperature cycling. When the vacuum in the system exceeds about 1" H20, the vacuum switch closes. The switch closure sends a signal to the PCM. In order to pass the non-intrusive small leak test, the ESIM switch must close within a calculated amount of time and within a specified amount of key-off events.

If the ESIM switch does not close as specified, the test is considered inconclusive and the intrusive engine running test will be run during the next key-on cycle. This intrusive test will run on the next cold engine running condition.

Conditions for running the intrusive test are

1. After the vehicle is started, the engine coolant temperature must be within 50° F (10° C) of ambient to indicate a cold start.
2. The fuel level must be between 12% and 88%.
3. The engine must be in closed loop.
4. Manifold vacuum must be greater than a minimum specified value.
5. Ambient temperature must be between 39° F and 98° F (4° C and 37° C) and the elevation level must be below 8500 feet (2591 meters).

The test is accomplished by the PCM activating the purge solenoid to create a vacuum in the evaporative system. The PCM then measures the amount of time it takes for the vacuum to dissipate. This is known as the vacuum decay method. If the switch opens quickly a large leak is recorded. If the switch opens after a predetermined amount of time, then the small leak matures. If the switch does not close, then a general evaporative failure is recorded. The purge monitor tests the integrity of the hose attached between the purge valve and throttle body/intake. The purge monitor is a two stage test and it runs only after the evaporative system passes the small leak test.

Even when all of the thresholds are met, a small leak won't be recorded until after the medium/large leak monitor has been run. This is accomplished by the PCM activating the purge solenoid to create a vacuum in the evaporative system. The PCM then measures the amount of time it takes for the vacuum to dissipate. This is known as the vacuum decay method. If the switch opens quickly a large leak is recorded. If the switch opens after a predetermined amount of time, then the small leak matures. If the medium/large leak test runs and the ESIM switch doesn't close, a general evaporative test is run. The purge solenoid is activated for approximately 10 seconds, increasing the amount of vacuum in the system. If the ESIM switch closes after the extended purge activation, a large leak fault is generated. If the switch doesn't close, a general evaporative system fault is generated.

The purge monitor tests the integrity of the hose attached between the purge valve and throttle body/intake. The purge monitor is a two stage test and it runs only after the evaporative system passes the small leak test.

Stage one of the purge monitor is non-intrusive. The PCM monitors the purge vapor ratio. If the ratio is above a calibrated specification, the monitor passes. Stage two is an intrusive test and it runs only if stage one fails. During the stage two test, the PCM commands the purge solenoid to flow at a specified rate to force the purge vapor ratio to update. The vapor ratio is compared to a calibrated specification and if it is less than specified, a one-trip failure is recorded.

The ESIM switch stuck closed monitor checks to see if the switch is stuck closed. This is a power down test that runs at key-off; when the PCM sees 0 RPM's, the purge solenoid is energized for a maximum of 30 seconds, venting any vacuum trapped in the evaporative system. If the switch opens or was open before the test began, the monitor passes. If the switch doesn't open, the monitor fails. This is a two-trip MIL. The star scan tool can be used to force the ESIM switch stick closed monitor to run.

The PCM also uses the ESIM to detect a loose or missing gas cap. The PCM controller looks for a change in the fuel level (25% minimum) and then gas cap is loose or missing. If a medium/large leak is detected, a loose gas cap light illuminates and a pending one-trip fault code is set. On the PCM, this is a three-trip fault before the code matures

The Evaporative System Integrity Monitor (ESIM) (3) is very similar to the NVLD. However, the design of the ESIM has been simplified and unlike the NVLD the ESIM does not require a solenoid. The ESIM mounts directly to the EVAP vapor canister, eliminating the need for a mounting bracket. The EVAP vapor canister is located in the left rear quarter panel behind the left rear wheelhouse splash shield.

Scheme 9

1. Disconnect and isolate the negative battery cable (2).
2. Remove the fuel tank filler cap.
3. Raise and support vehicle.
4. Remove left rear wheel and tire.
5. Remove the left rear wheelhouse splash shield. Refer to «SHIELD, SPLASH, WHEELHOUSE, REMOVAL»(ref-465921-S10952698702012042300000) . NOTE: When removing the fresh air hose, remove the hose at the fresh air filter first, this will eliminate the risk of breaking the nipple from the ESIM during removal.
6. Carefully remove the ESIM fresh air hose (1) at the fresh air filter.
7. Disconnect the electrical connector (2) at the ESIM.
8. A lock tab (see arrow in illustration) is used on the back of the switch. Push the lock tab towards ESIM switch while rotating counterclockwise 1/4 turn for removal. The fresh air lines and hoses from the ESIM must have a clear opening to the atmosphere. Check the fresh air lines, including the fresh air filter, for obstructions or restrictions at the ESIM. If a restriction is present, the system will not allow free flow passage of clean air, and an early shut off of the fuel fill nozzle may occur during refueling.
9. Clean any dirt from ESIM switch, lines and EVAP canister opening.
10. Inspect the ESIM O-ring, replace if necessary.

1. A lock tab (see arrow in illustration) is used on the back of the switch. Position the ESIM switch into the EVAP canister and rotate switch until the electrical connector is in 3 O'clock position and the locking tab locks into position.
2. Connect the ESIM fresh air hose (1) at the fresh air filter.
3. Connect the electrical connector (2) at the ESIM.
4. Install the left rear wheelhouse splash shield. Refer to «SHIELD, SPLASH, WHEELHOUSE, INSTALLATION»(ref-465921-S28556323522012042300000) .
5. Install left rear wheel and tire.
6. Lower the vehicle.
7. Connect the negative battery cable (2).
8. Install the fuel tank filler cap.
9. Start the engine and check for leaks.

Scheme 10

Scheme 11

1. Remove the hose (1) from the PCV valve (2).
2. Remove the three screws (2) and the PCV valve (1) from the right cylinder head cover.

INSTALLATION - PCV VALVE

1. Clean and inspect the sealing surfaces of the PCV valve and cylinder head cover. The seal can be reused provided it is free of cuts or tears.
2. Install the PCV valve seal in the cylinder head cover.
3. Install the PCV valve (1) with three screws (2). Tighten the screws to 4 N.m (35 in. lbs.).
4. Install the PCV hose (1) between the upper intake manifold and the PCV valve (2).

Scheme 12

The PCV valve (1) is located at the top right rear of the intake manifold.

Scheme 13

1. The PCV valve is sealed to the intake manifold with two O-rings (2).
2. Remove the PCV valve by rotating counter-clockwise 90 degrees until the locating tabs (3) have been released.
3. Pull the PCV valve straight up and remove from the intake manifold.
4. Check the condition of the two PCV valve O-rings (2), replace if necessary.

1. Check the condition of the two PCV valve O-rings (2), replace if necessary.
2. Clean the PCV valve mounting surface of the intake manifold opening.
3. Apply engine oil to the two O-rings (2) on the PCV valve.
4. Position the PCV valve (1) into intake manifold and rotate 90 degrees clockwise until the locating tabs are locked in place.