Emissions Control: Removal & Installation Dodge Dakota III рестайлинг

REMOVAL/INSTALLATION

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.

INSTALLATION

1. Install solenoid assembly (2) to mounting bracket (1).
2. Connect vacuum lines (5) and (6).
3. Connect electrical connector (3).
4. The vapor/vacuum lines and hoses must be firmly connected. Check the vapor/vacuum lines at the ESIM switch, pump filter and EVAP canister purge solenoid for damage or leaks. If a leak is present, a Diagnostic Trouble Code (DTC) may be set.

Scheme 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 10

The ESIM assembly consists of a housing, a small weight and a large weight that serve as check valves, a diaphragm, a switch and a cover. 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.

Scheme 11

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.

The ESIM consists of housing, two check valves (sometimes referred to as weights), a diaphragm, a switch and a cover. The larger check valve seals for pressure and the smaller one seals for vacuum.

During refueling, pressure is built up in the evaporative system. When pressure reaches approximately.5 inches of water, the large check valve 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 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 EVAP. system during engine off conditions. If the EVAP. 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

REMOVAL

The ESIM (EVAP System Integrity Monitor) switch is attached to the EVAP canister and is usually not serviceable. Replace the switch by replacing the EVAP canister. See EVAP canister for removal/installation.

If servicing separately, refer to the following

Scheme 12

The ESIM switch (2) is located on the EVAP canister (1) The illustration displays a typical EVAP Canister and a typical ESIM switch.

Scheme 13

Scheme 14

1. Remove both plastic lines from switch by folding line tabs (2).
2. Disconnect electrical connector at switch.
3. Clean any dirt from ESIM switch and its lines.
4. A lock tab (see arrow in illustration) is used on the back of the switch. Push lock tab towards switch while rotating switch counterclockwise 1/4 turn for removal.
5. 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. Also check the routing to the exit to atmosphere. 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 fuel fill.

The following illustrations display a TYPICAL EVAP Canister and a typical ESIM switch. After installing any ESIM switch, the electrical connector on the switch must be in the 3 O'clock position. This step must be done for proper ESIM switch operation.

1. 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. Also check the routing to the exit to atmosphere. 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 fuel fill.
2. Be sure O-ring (2) and EVAP canister opening are clean. 1 - EVAP Canister 2 - ESIM Switch 3 - Electrical Connector CAUTION: The electrical connector (3) on the ESIM switch must be in 3 O'clock position after installation. This step must be done for proper switch operation.
3. Position ESIM switch (2) into EVAP canister (1) and rotate until electrical connector is in 3 O'clock position (3).
4. Connect electrical connector.
5. Connect plastic lines to ESIM switch.

Scheme 15

The PCV valve is located at the rear of the left cylinder head.

Scheme 16

1. Remove line (1) and rubber connector hose from PCV valve.
2. Un-thread PCV valve (3) from metal fitting (2).

Scheme 17

1. Check condition of PCV valve rubber O-ring (2).
2. Clean fitting (2).
3. Install PCV valve (3) into fitting (2).
4. Install PCV line (1) and rubber connector to valve.

Scheme 18

The PCV valve (2) is mounted into the top/rear of the left valve cover.

1. Disconnect plastic line (1) from end of PCV valve.
2. Use a small screwdriver to disengage PCV valve from valve cover.

1. Clean out PCV valve opening at valve cover.
2. Check condition of PCV valve o-ring.
3. Apply engine oil to o-ring.
4. Place PCV valve (2) into valve cover.
5. Attach plastic line (1) to valve.

1. Clean gasket area (1) at rear of left cylinder head where it joins base of EGR valve.
2. Clean EGR tube where it joins EGR valve.
3. Position new gasket between EGR valve and cylinder head.
4. Position EGR valve to cylinder head. Install and tighten two bolts (2). Torque to 9 N.m (80 in. lbs.).
5. Position new gasket (3) between EGR tube flange and EGR valve assembly.
6. Position EGR tube (1) to side of EGR valve. Position end of tube (6) into intake manifold. Install two bolts (2). Torque to 11 N.m (8.5 ft. lbs.).
7. Connect electrical connector (3) to top of EGR valve solenoid (1).
8. Install EVAP canister purge solenoid (2) by slipping assembly to tongue-type bracket (1).
9. Connect negative battery cable.
10. Using a diagnostic scan tool, erase any previously recorded DTC's (Diagnostic Trouble Codes).

Scheme 19

The electronic EGR valve and solenoid assembly (4) is attached to the rear of the left cylinder head. An exhaust gas routing tube (3) connects the EGR valve to the intake manifold.

Scheme 20

1. Use a diagnostic scan tool to record any DTC's (Diagnostic Trouble Codes).
2. Disconnect and isolate the negative battery cable.
3. Remove EVAP solenoid (2). Refer to «SOLENOID, Evaporative Emissions Purge»(ref-352639-S24335862112010010600000) Removal and Installation for procedures.
4. Remove electrical connector (5) at top of EGR valve solenoid.
5. Remove tube mounting bolt (1) at intake manifold.
6. Remove two bolts (4) connecting EGR tube (1) to valve assembly.
7. Remove gasket located between EGR tube flange and EGR valve assembly.
8. Remove two EGR valve mounting bolts (5).
9. Separate valve assembly (3) from engine.
10. Remove and discard metal gasket located between cylinder head and valve assembly.

1. Clean area at rear of left cylinder head where it joins base of EGR valve.
2. Clean EGR tube where it joins EGR valve.
3. Position new gasket between EGR valve and cylinder head.
4. Position EGR valve to cylinder head. Install and tighten two bolts (5). Torque to 9 N.m (80 in. lbs.).
5. Position new gasket between EGR tube flange and EGR valve assembly.
6. Position EGR tube (1) to side of EGR valve and into intake manifold. Install two bolts (4) finger tight (temporarily).
7. Install EGR tube flange bolt (1) at intake manifold. Torque to 11 N.m (8.5 ft. lbs.).
8. Connect electrical connector (5) to top of EGR valve solenoid (4).
9. Do a final tightening of two EGR tube bolts (4). Torque to 11 N.m (8.5 ft. lbs.).
10. Install EVAP solenoid (2). Refer to «SOLENOID, Evaporative Emissions Purge»(ref-352639-S24335862112010010600000) Removal and Installation for procedures.
11. Connect negative battery cable.
12. Using a diagnostic scan tool, erase any previously recorded DTC's (Diagnostic Trouble Codes).