Overview
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SPECS - TORQUE
DESCRIPTION N.m Ft. Lbs. Inch Lbs.
EVAP Canister Mounting 95
11 -Nut/Bolt PCV Valve 12 - 106 EGR Valve-to-Cyl. Head 28 21 248 Bolts - 3.7L ERG Tube-to-EGR Valve 13 9.6- 115 Bolts EGR Tube-to-Intake 4 - 35 Manifold Bolts
SOLENOID-EVAP/PURGE
ORVR
The ORVR (On-Board Refueling Vapor Recovery) system consists of a unique fuel tank, flow management valve, fluid control valve, one-way check valve and vapor canister.
ORVR
The ORVR (On-Board Refueling Vapor Recovery) system is used to remove excess fuel tank vapors. This is done while the vehicle is being refueled.
Fuel flowing into the fuel filler tube (approx. 1" I.D.) creates an aspiration effect drawing air into the fuel fill tube. During refueling, the fuel tank is vented to the EVAP canister to capture escaping vapors. With air flowing into the filler tube, there are no fuel vapors escaping to the atmosphere. Once the refueling vapors are captured by the EVAP canister, the vehicle's computer controlled purge system draws vapor out of the canister for the engine to burn. The vapor flow is metered by the purge solenoid so that there is no, or minimal impact on driveability or tailpipe emissions.
As fuel starts to flow through the fuel fill tube, it opens the normally closed check valve and enters the fuel tank. Vapor or air is expelled from the tank through the control valve and on to the vapor canister. Vapor is absorbed in the EVAP canister until vapor flow in the lines stops. This stoppage occurs following fuel shut-off, or by having the fuel level in the tank rise high enough to close the control valve. This control valve contains a float that rises to seal the large diameter vent path to the EVAP canister. At this point in the refueling process, fuel tank pressure increases, the check valve closes (preventing liquid fuel from spiting back at the operator), and fuel then rises up the fuel filler tube to shut off the dispensing nozzle.
VACUUM LINES
A vacuum schematic for emission related items can be found on the VECI label. Refer to Vehicle Emission Control Information (VECI) Label for schematic location.
SWITCH-EVAP SYSTEM MONITOR
HEATER-CRANKCASE 2.8L DIESEL
Removal
The crankcase heater (2) is located in the hose (1) leading to the crankcase breather (6).
1
Disconnect electrical connector (5).
2
Separate hose (1) from heater.
3
Separate heater from hose (3).
Installation
The crankcase heater (2) is located in the hose (1) leading to the crankcase breather (6).
1
Twist heater (2) into hose (3).
2
Twist hose (1) into heater.
3
Connect electrical connector (5).
VALVE - EGR 3.7L
EXHAUST GAS RECIRCULATION - 2.8L DIESEL
Torque specifications
| DESCRIPTION | N.m | Ft. Lbs. | In. Lbs. |
| EGR Mounting Bolts - | 15 | 11 | - |
2.8L Diesel EGR Airflow Control 11 8 - Valve - 2.8L Diesel
GLOSSARY OF TERMS
APPS Accelerator Pedal Position Sensor AAT Ambient Air Temperature ABS Anti-Lock Brake System ASD Auto Shut Down BARO Barometric CGW Central Gateway CKP Crankshaft Position Sensor CMP Camshaft Position Sensor CMTC Compass/Mini-Trip Computer DCHA Diesel Cabin Heater Assist DLC Data Link Connector DTC Diagnostic Trouble Code EATX Electronic Automatic Transaxle ECT Engine Coolant Temperature ECM Engine Control Module EGR Exhaust Gas Recirculation ETC Electronic Throttle Control GEN Generator GPEC Global Powertrain Engine Controller FCM Front Control Module FDCM Final Drive Control Module IAT Intake/Inlet Air Temperature IAC Idle Air Control IOD Ignition Off-Draw IPM Integrated Power Module JTEC Jeep Truck Engine Controller KS Knock Sensor LDP Leak Detection Pump MAP Manifold Air Pressure MDS Multi Displacement System MIC Mechanical Instrument Cluster MIL Malfunction Indicator Lamp MTV Manifold Tuning Valve NGC Next Generation Controller NVLD Natural Vacuum Leak Detection O2S Oxygen Sensor
OBD On Board Diagnostic PDC Power Distribution Center PCI Programmable Communication Interface PCM Powertrain Control Module PCV Positive Crankcase Ventilation PEP Peripheral Expansion Port SBEC Single Board Engine Controller SCM Steering Control Module S/C Speed Control SKIM Sentry Key Immobilizer Module SKIS Sentry Key Immobilizer System SKREEM Sentry Key Remote Entry Module SKREES Sentry Key Remote Entry System SOL Solenoid SRV Short Runner Valve TCM Transmission Control Module TCC Torque Converter Clutch TIP Throttle Inlet Pressure TIPM Totally Integrated Power Module TP Throttle Position TPMS Tire Pressure Monitor System TRS Transmission Range Sensor VSS Vehicle Speed Sensor/Signal WCM Wireless Control Module
OBDII MONITOR RUN PROCESS
The following procedure has been established to assist technicians in the field with enabling and running OBD II Monitors. The order listed in the following procedure is intended to allow the technician to effectively complete each monitor and to set the CARB Readiness Status in the least time possible.
NOTE: Once the monitor run process has begun, do not turn off the ignition. By turning the ignition key off, monitor enabling conditions will be lost. EVAP Monitor runs after key off. By performing a Battery Disconnect, or Selecting Erase DTCs, the CARB Readiness and all additional OBD II information will be cleared.
Monitor Preliminary Checks:
1. Plug a scan tool into the vehicle's Data Link Connector (DLC). 2. Turn the ignition, KEY ON - ENGINE OFF. Watch for MIL lamp illumination during the bulb check.
MIL lamp must have illuminated, if not, repair MIL lamp. 3. Using a scan tool check for Powertrain related DTCs. Verify that No Emissions Related DTCs are Present. If an Emissions DTC is Present, the OBD II Monitors may not run and the CARB Readiness will not update. The Emissions related DTC, will need to be repaired, then cleared. By clearing DTCs, the OBD Monitors will need to be run and completed to set the CARB Readiness Status.
Using the scan tool check the CARB Readiness Status.
Do all the CARB Readiness Status Locations read YES?
YES - all monitors have been completed and this vehicle is ready to be I/M or Emission Tested. NO - then the following procedure needs to be followed to run/complete all available monitors.
NOTE: Only the monitors, which are not YES in the CARB Readiness Status, need to be completed. Specific criteria need to be met for each monitor. The most efficient order to run the monitors has been outlined below, including suggestions to aid the process.
Evaporative Emission System Leak Detection with Purge Monitor
This monitor requires a cool down cycle, usually an overnight soak for at least 8 hours without the engine running. The ambient temperature must decrease overnight - parking the vehicle outside is advised. To run this test the fuel level must be between 15-85% full. Criteria for EVAP monitor:
Engine off time greater than one hour. Fuel Level between 15% and 85%. Start Up ECT and IAT within 10°C (18°F). Vehicle started and run until Purge Monitor reports a result.
NOTE: If the vehicle does not report a result and the conditions where correct. It may take up to two weeks to fail the small leak monitor. DO NOT use this test to attempt to determine a fault. Use the appropriate service information procedure for finding a small leak. If there are no faults and the conditions are correct this test will run and report a pass. Note the Small leak test can find leaks less than 10 thousands of an inch. If a small leak is present it takes approximately one week of normal driving to report a failure.
Catalyst / O2 Monitor
The Catalyst and O2 Monitor information are acquired and processed at the same time. Most vehicles will need to be driven at highway speed (less than 50 mph) (73km/h) for a few minutes. Some vehicles run the monitor at idle in drive. If the vehicle is equipped with a manual transmission, using 4th gear may assist in meeting the monitor running criteria.
Engine RPM between 1200 to 3000. Engine temperature greater than 70°C (158°F) Engine run time greater than 92 seconds MAP between 10 - 20 kPa (7.5 - 15 Hg) Vehicle speed between 20 - 70 mph (29-103 km/h)
EGR Monitor
After the vehicle has reached the below conditions and during a throttle decel the EGR monitor will run.
Engine RPM between 1375 - 2500 Engine temperature greater than 70°C (158°F) Engine run time greater than 125 seconds Vehicle speed between 25 - 70 mph (37-103 km/h)
O2 Sensor Heater Monitor
This monitor is now continuously running once the heaters are energized. Pass information will be processed at power down.
Mis-Fire Monitor
The Misfire Monitor is a continuous two-trip monitor. The monitor uses two different tests/counters:
NOTE: The Adaptive Numerator must be learned before the PCM will run the Mis-Fire Monitor. The PCM updates the Adaptive Numerator at every key-ON, and is relearned after battery disconnect. The Misfire Monitor will not run until the Adaptive Numerator has updated since the last battery disconnect. If the Adaptive Numerator is equal to the default value then the PCM knows that the Adaptive Numerator has not been learned and does not permit the Misfire Monitor to run. If the Adaptive Numerator exceeds a calibrated percentage, the PCM sets a DTC for CKP NOT LEARNED and illuminates the MIL.
200 Revolution Counter - Looks for misfire that can cause immediate catalyst damage. 1000 Revolution Counter - Looks for misfire that can cause emissions to increase 1.5 times the Federal Test Procedure (FTP) standards. This test must also identify misfire percentages that might cause a "durability demonstration vehicle" to fail an Inspection and Maintenance Program tailpipe emissions test.