Common Jeep Sensors/Valves - North American Grand Cherokee Association
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Old 07-09-2007, 12:48 PM   #1
SOLITUDE
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Default Common Jeep Sensors/Valves

AUTO SHUT DOWN (ASD) RELAY—PCM OUTPUT
  • The ASD relay is located in the power distribution center (PDC). For the location of this relay within the PDC, refer to label under PDC cover.

    The ASD supplies battery voltage to the fuel pump, fuel injector, ignition coil, generator field winding and oxygen (O2S) sensor heating element. The ground circuit for the coil in the ASD relay is controlled by the powertrain control module (PCM). The PCM operates the relay by switching the ground circuit on and off.

    The fuel pump relay is controlled by the PCM through same circuit that the ASD relay is controlled.

    ANY time you get a no start, wait 5-10 minutes to see if it resets itself, if not remove the relay, crank over jeep 4-5 times, replace relay, that will reset it and start up. If not, switch relay with the one next to it (if it was bad). The ASD will turn off the jeep if you over heat it, or oil level / pressure too low, and sometimes just for the fun of it, always check this first.

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CRANKSHAFT POSITION SENSOR
  • 4.0L 6 CYLINDER ENGINES WITHOUT 42RE AUTOMATIC TRANSMISSION:
    The crankshaft position sensor is mounted to the transmission bellhousing with two bolts at the left/rear side of the engine block.
    4.0L 6 CYLINDER ENGINES WITH 42RE AUTOMATIC TRANSMISSION:
    The crankshaft position sensor is mounted to the transmission bellhousing with one bolt at the left/rear side of the engine block.

    5.2L V-8 ENGINE
    On 5.2L engines, the sensor is bolted to the top of cylinder block near the rear of the right cylinder head. Engine speed and crankshaft position are provided through the crankshaft position sensor. The sensor generates pulses that are the input sent to the powertrain control module (PCM). The PCM interprets the sensor input to determine the crankshaft position. The PCM then uses this position, along with
    other inputs, to determine injector sequence and ignition timing.

    The sensor is a hall effect device combined with an internal magnet. It is also sensitive to steel within a certain distance from it.

    SENSOR OPERATION—4.0L ENGINE
    The flywheel/drive plate has groups of four notches at its outer edge. On 4.0L engines there are three sets of notches.

    The notches cause a pulse to be generated when they pass under the sensor. The pulses are the input to the PCM. For each engine revolution there are there are 3 groups of four pulses generated on 4.0L 6 cylinder engines.

    The trailing edge of the fourth notch, which causes the pulse, is four degrees before top dead center (TDC) of the corresponding piston.
    The engine will not operate if the PCM does not receive a crankshaft position sensor input. For component testing, refer to the Diagnostics/Service Procedures section of this group. For removal and installation of this sensor, refer to the Component Removal/Installation section of this group.

    SENSOR OPERATION—5.2L V-8 ENGINE
    On 5.2L engines, the flywheel/drive plate has 8 single notches, spaced every 45 degrees, at its outer edge.

    The notches cause a pulse to be generated when they pass under the sensor. The pulses are the input to the PCM. For each engine revolution, there are 8 pulses generated on 5.2L V-8 engines.

    The engine will not operate if the PCM does not receive a crankshaft position sensor input.

    For component testing, refer to the Diagnostics/Service Procedures section of this group. For removal and installation of this component, refer
    to the Component Removal/Installation section of this group.

    REMOVAL—4.0L 6 CYLINDER ENGINE WITHOUT 42RE TRANSMISSION
    The crankshaft position sensor is mounted to the transmission bellhousing with two bolts at the left/rear side of the engine block.

    (1) Near the rear of the intake manifold, disconnect the pigtail harness on the sensor from the main electrical harness.
    (2) Raise and support the vehicle.
    (3) Remove the two sensor mounting bolts (Fig. 6).
    (4) Remove the sensor.
    (5) Remove clip from sensor wire harness.

    INSTALLATION
    (1) Install the sensor flush against the opening in the transmission housing.
    (2) Install and tighten the two sensor mounting bolts to 19 Nzm (14 ft. lbs.) torque.
    CAUTION: The two bolts used to secure the sensor to the transmission are specially machined to correctly
    space the unit to the flywheel. Do not attempt to install any other bolts.

    (3) Lower the vehicle.
    (4) Connect the electrical connector to the sensor.
    (5) Install clip on sensor wire harness.

    REMOVAL—4.0L ENGINE WITH 42RE TRANSMISSION
    On models with a 4.0L engine and 42 RE automatic transmission, the sensor uses a single slotted hole to adjust its depth. A paper/cardboard type spacer with self-adhesive is attached to the bottom of the sensor to set this depth. After the engine has been started (and after sensor installation), this temporary spacer will be sheared off. New factory replacement sensors are equipped with this spacer. If the original sensor is to be reinstalled, such as with transmission and/or flywheel removal, a new spacer MUST be installed.
    (1) Near the rear of the intake manifold, disconnect the pigtail harness (on the sensor) from the main electrical harness.
    (2) Remove the nut holding sensor wire clip to fuel rail mounting stud.
    (3) Remove the one sensor mounting bolt.
    (4) Remove the sensor.
    (5) Remove clip from sensor wire harness.

    INSTALLATION
    (1) Be sure the paper/cardboard spacer has been installed to the bottom of the new sensor. If original sensor is being reinstalled (such as with
    transmission or flywheel removal), clean bottom of the sensor before installation. Obtain a new spacer and remove the paper backing. Install the self-adhesive side to bottom of sensor. This spacer MUST be installed. If spacer is not installed, sensor will be damaged when engine is started.
    (2) Position sensor to transmission bellhousing and install mounting bolt finger tight.
    (3) Gently seat (push down) the sensor until the paper spacer contacts the outer edge of the flywheel.
    (4) Tighten sensor mounting bolt to 17-to-21 Nzm (13-to-16 ft. lbs.) torque.
    (5) Connect the electrical connector to sensor.
    (6) Install the clip to sensor wire harness.
    (7) Install clip over fuel rail mounting stud. Install clip mounting nut.

    REMOVAL—5.2L V-8 ENGINE
    The sensor is bolted to the top of the cylinder block near the rear of right cylinder head.
    (1) Remove the spark plug cable loom and spark plug cables from valve cover mounting stud at rear of right valve cover. Position spark plug cables to top of valve cover.
    (2) Remove the right exhaust manifold heat shield nuts/bolts and remove heat shield.
    (3) Disconnect 2 hoses at exhaust gas recirculation (EGR) valve. Note position of hoses at EGR valve before removal.
    (4) Disconnect electrical connector and hoses at electric EGR transducer (EET). Note position of hoses at EET before removal.
    (5) Remove 2 EGR valve mounting bolts and remove EGR valve. Discard old EGR gasket.
    (6) Disconnect electrical connector at engine oil pressure sending unit.
    (7) To prevent damage to oil pressure sending unit,
    (8) Loosen EGR tube mounting nut at intake manifold.
    (9) Remove 2 EGR tube mounting bolts at exhaust manifold and remove EGR tube. Discard old gasket at exhaust manifold.
    (10) Disconnect crankshaft position sensor pigtail harness from main wiring harness.
    (11) Remove 2 sensor (recessed hex head) mounting bolts and remove sensor.

    INSTALLATION—5.2L ENGINE
    (1) Position crankshaft position sensor to engine and install mounting bolts. Tighten bolts to 8 Nzm (70 in. lbs.) torque.
    (2) Connect main harness electrical connector to sensor.
    (3) Clean the EGR tube and exhaust manifold (at EGR tube mounting point) of any old gasket material.
    (4) Install a new gasket to exhaust manifold end of EGR tube and install EGR tube to both manifolds. Tighten tube mounting nut at intake manifold. Tighten 2 mounting bolts at exhaust manifold to 23 Nzm (204 in. lbs.) torque.
    (5) Coat the threads of the oil pressure sending unit with thread sealant. Do not allow any of the thread sealant to get into the sending unit opening, or the opening at the engine. Install sending unit to engine and tighten to 14 Nzm (130 in. lbs.) torque. Install electrical connector to sending unit.
    (6) Clean the intake manifold and EGR valve of any old gasket material.
    (7) Install a new EGR valve gasket at intake manifold.
    (8) Install EGR valve to intake manifold. Tighten 2 EGR bolts to 23 Nzm (200 in. lbs.) torque.
    (9) Position EET and install its electrical connector. Connect hoses between EGR valve and EET. Connect hose between main vacuum harness and EET.
    (10) Install spark plug cable loom and spark plug cables to valve cover mounting stud.
    (11) Install heat shield at right exhaust manifold.

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ENGINE COOLANT TEMPERATURE SENSOR (CTS)
  • The sensor provides an input voltage to the powertrain
    control module (PCM) relating coolant temperature. The PCM uses this input, along with inputs from other sensors, to determine injector pulse width and ignition timing. As coolant temperature varies, the coolant temperature sensor resistance will change, resulting in a different input voltage to the PCM.

    When the engine is cold, the PCM will operate in the Open Loop Cycle. It will demand slightly richer air-fuel mixtures and higher idle speeds, until normal operating temperatures are reached. Refer to Modes Of Operation in Group 14, Fuel System for a description of Open and Closed Loop operation.

    This sensor is installed in the thermostat housing on 4.0L 6 cylinder engines.

    This sensor is installed in the intake manifold near the thermostat housing on 5.2L V-8 engines.

    WARNING: HOT, PRESSURIZED COOLANT CAN CAUSE INJURY BY SCALDING. COOLING SYSTEM MUST BE PARTIALLY DRAINED BEFORE REMOVING THE COOLANT TEMPERATURE SENSOR. REFER TO GROUP 7, COOLING.

    REMOVAL—4.0L 6 CYLINDER ENGINE
    The sensor is installed in the thermostat housing on 4.0L engines.
    (1) Drain cooling system until the coolant level is below the cylinder head. For cooling system draining, refer to Group 7, Cooling.
    (2) Disconnect the coolant temperature sensor wire connector.
    (3) Remove the sensor from the thermostat housing

    INSTALLATION—4.0L ENGINE
    (1) Install coolant temperature sensor into the thermostat housing. Tighten to 28 Nzm (21 ft. lbs.) torque.
    (2) Connect the wire connector.
    (3) Fill the cooling system. Refer to group 7, Cooling System.

    REMOVAL—5.2L V-8 ENGINE
    The engine coolant temperature sensor on the 5.2L engine is located in a water passage of the intake manifold next to the thermostat housing.
    (1) Partially drain cooling system. Refer to Group 7, Cooling.
    (2) Disconnect electrical connector from sensor.
    (3) Engines with air conditioning: When removing the connector from sensor, do not pull directly on wiring harness. Fabricate an L-shaped hook tool from a coat hanger (approximately eight inches long). Place the hook part of tool under the connector for removal. The connector is snapped onto the sensor. It is not equipped with a lock type tab.
    (4) Remove sensor from intake manifold.

    INSTALLATION—5.2L ENGINE
    (1) Install sensor.
    (2) Tighten to 7 Nzm (5.5 ft. lbs.) torque.
    (3) Connect electrical connector to sensor. The sensor connector is symmetrical (not indexed). It can be installed to the sensor in either direction.
    (4) Replace any lost engine coolant. Refer to Group 7, Cooling System.

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EGR OPERATION—5.2L ENGINE
  • The Electric Exhaust Gas Recirculation Transducer(EET) is a back pressure transducer and an electric vacuum solenoid combined into a single unit. The vacuum solenoid portion of the EET receives its electrical signal from the powertrain control module (PCM). Using this signal, the solenoid regulates the vacuum flowing through to the transducer portion of the EET. The back pressure transducer measures the amount of exhaust gas back pressure on the exhaust side of the EGR valve. It then varies the strength of the vacuum signal applied to the EGR valve. The transducer uses this back pressure signal to provide the correct amount of exhaust gas recirculation under all conditions.

    The vacuum supply for the EGR valve is controlled by the EET. The electrical solenoid portion of the EET is controlled by the powertrain control module (PCM). The PCM monitors engine coolant temperature and other operating conditions to determine when EGR operation is desired. Refer to Open Loop/Closed Loop Modes of Operation in Group 14, Fuel Systems for a description of EGR solenoid operation based on engine operating conditions.

    If the electrical connector to the EET is disconnected, or the electrical signal is lost, the EGR valve will operate at all times. This results in poor engine performance and reduced driveability during certain operating conditions.

    Vacuum flows between the solenoid portion of the EET and the transducer portion of the EET. This happens only when the solenoid is not electrically energized. The transducer is connected to the EGR valve by a vacuum hose and a back pressure hose.The transducer is controlled by exhaust back pressure and is ported to the exhaust manifold through a hose connecting it to the bottom of the EGR valve. Vacuum will be supplied to the EGR valve and EGR operation will begin when:
    * The electrical solenoid portion of the EET is not energized.
    * The engine back pressure entering the EGR valve inlet is strong enough to close the transducer bleed valve.

    If back pressure is not strong enough to close the transducer bleed valve, the transducer will bleed off the vacuum preventing EGR operation. When the electrical solenoid portion of the EET is de-energized by the powertrain control module (PCM), vacuum flows to the transducer. The transducer is connected to the engine exhaust system by a small hose that connects to the base of the EGR valve.

    The vacuum section of the transducer is controlled by exhaust system back pressure. When back pressure is high enough it will close a bleed valve in the transducer allowing vacuum to actuate the EGR valve. If back pressure does not close the bleed valve, vacuum will be bled off.

    EGR SYSTEM ON-BOARD DIAGNOSTICS
    The powertrain control module (PCM) performs an On-Board Diagnostic (OBD) check of the EGR system on all vehicles. The diagnostic system uses the Electric EGR Transducer (EET) for the system tests.

    The OBD check activates only during selected engine/driving conditions. When the conditions are met, the PCM energizes the EET solenoid to disable the EGR. The PCM checks for a change in the oxygen sensor signal. If the air-fuel mixture goes lean, the PCM will attempt to enrichen the mixture. The PCM registers a Diagnostic Trouble Code (DTC) if the EGR system has failed or degraded. After registering a DTC, the PCM turns the Malfunction Indicator Lamp (MIL) on. (The Malfunction Indicator Lamp was formerly referred to as the Check Engine Lamp). The Malfunction Indicator Lamp indicates the need for immediate service.

    If a malfunction is indicated by the Malfunction Indicator Lamp and a DTC for the EGR system was set, check for proper operation of EGR system. Use
    the following: System Test, EGR Gas Flow Test and EGR Diagnosis Chart. If the EGR system tests properly, check the system using the DRB scan tool. or use of the DRB, refer to the appropriate Powertrain Diagnostics Procedure
    service manual.

    EGR SYSTEM SERVICE—5.2L ENGINE
    A malfunctioning EGR system can cause engine spark knock, sags or hesitation, rough idle, engine stalling and poor driveability. To be sure of proper operation of the EGR system, inspect all passages for blockage. Check moving parts for binding. Inspect the complete system for leaks. Replace system components or hoses that are leaking.

    Inspect all hose connections between throttle body, intake manifold, EGR valve and EGR purge solenoid. Replace any vacuum harness components that are leaking or damaged.

    Refer to EGR Control System Test and EGR Gas Flow Test to check EGR System operation.

    EGR GAS FLOW TEST—5.2L ENGINE
    (1) Disconnect hose from EGR valve and connect a hand vacuum pump to EGR valve nipple. Apply a minimum of 12 inches vacuum the valve.
    (2) The engine should now idle roughly or stall. If this occurs, the valve is performing correctly. Proceed to Electric EGR Transducer Test.
    (3) If the engine idle speed did not change, remove the EGR valve and inspect the valve and the exhaust passage in the manifold for blockage. Repair as necessary. If blockage is not present, replace the EGR valve.

    ELECTRIC EGR TRANSDUCER (EET)—5.2L ENGINE TESTING ELECTRIC SOLENOID PORTION OF TRANSDUCER
    (1) Bring the engine to normal operating temperature. Operate at idle speed. Test the EET as follows:
    (2) Check vacuum at EET vacuum source. Disconnect the hose and attach a vacuum gauge to it.
    (3) Vacuum should be a minimum of 15 inches:
    * If vacuum is low, check the line for kinks, twists, or a loose connection at vacuum connector or intake manifold.
    * If vacuum is correct, remove gauge. Connect the vacuum line and proceed to next step.
    (4) Check EET operation using the appropriate Powertrain Diagnostic Procedures service manual. Refer to this manual for use of the DRB scan tool and repair EET as necessary.

    TESTING VACUUM PORTION OF TRANSDUCER
    (1) Disconnect the EET vacuum lines, back pressure line and electrical connector. Remove transducer.
    (2) Plug the EET EGR valve port.
    (3) Apply 1-2 pounds air pressure to exhaust back pressure port. Air pressure can be supplied with a hand operated air pump or compressed air (regulated to correct psi).
    (4) Apply a minimum of 12 inches of vacuum to vacuum supply port. Replace the EET if it will not hold vacuum.

    For electrical tests of the EET and its circuitry, refer to the appropriate Powertrain Diagnostic Procedures service manual and use the DRB scan tool.

    VALVE REMOVAL
    The EGR valve and the Electric EGR Transducer (EET) are serviced as one unit on the 5.2L engine.
    (1) Disconnect vacuum hose to EGR valve/transducer assembly. Note position of hoses on the EGR valve and transducer for easier installation.
    (2) Remove EGR mounting bolts.
    (3) Remove EGR valve and gasket. Discard old gasket. Clean intake manifold mating surface and check for cracks.

    VALVE INSTALLATION
    (1) Place new EGR gasket on intake manifold.
    (2) Install EGR valve. Tighten mounting bolts to 23 Nzm (200 in. lbs.) torque.
    (3) Connect vacuum hose to valve/transducer assembly.

    TUBE REMOVAL
    (1) Remove the spark plug cable loom and spark plug cables from valve cover mounting stud at rear of right valve cover. Position spark plug cables to top of valve cover.
    (2) Remove the right exhaust manifold heat shield nuts/bolts and remove heat shield.
    (3) Disconnect 2 hoses at Exhaust Gas Recirculation (EGR) valve. Note position of hoses at EGR valve before removal.
    (4) Disconnect electrical connector and hoses at electric EGR transducer (EET). Note position of hoses at EET before removal.
    (5) Remove 2 EGR valve mounting bolts and remove EGR valve. Discard old EGR gasket.
    (6) Disconnect electrical connector at engine oil pressure sending unit.
    (7) To prevent damage to oil pressure sending unit, a special tool, such as number C-4597 must be used. Remove sending unit from engine.
    (8) Loosen EGR tube mounting nut at intake manifold.
    (9) Remove 2 EGR tube mounting bolts at exhaust manifold and remove EGR tube. Discard old gasket at exhaust manifold.
    (10) Remove EGR tube from vehicle.

    TUBE INSTALLATION
    (1) Clean the EGR tube and exhaust manifold (at EGR tube mounting point) of any old gasket material.
    (2) Install a new gasket to exhaust manifold end of EGR tube and install EGR tube to both manifolds. Tighten tube mounting nut at intake manifold. Tighten 2 mounting bolts at exhaust manifold to 23 Nzm (204 in. lbs.) torque.
    (3) Coat the threads of the oil pressure sending unit with thread sealant. Do not allow any of the thread sealant to get into the sending unit opening, or the opening at the engine. Install sending unit to engine and tighten to 14 Nzm (130 in. lbs.) torque. Install electrical connector to sending unit.
    (4) Clean the intake manifold and EGR valve of any old gasket material.
    (5) Install a new EGR valve gasket at intake manifold.
    (6) Install EGR valve to intake manifold. Tighten 2 EGR bolts to 23 Nzm (200 in. lbs.) torque.
    (7) Position EET and install its electrical connector. Connect hoses between EGR valve and EET. Connect hose between main vacuum harness and EET.
    (8) Install spark plug cable loom and spark plug cables to valve cover mounting stud.
    (9) Install heat shield at right exhaust manifold.

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IDLE AIR CONTROL (IAC) MOTOR—PCM OUTPUT
  • The IAC motor is mounted on the throttle body and is controlled by the powertrain control module (PCM).

    The throttle body has an air control passage that provides air for the engine at idle (the throttle plate is closed). The IAC motor pintle protrudes into the air control passage and regulates air flow through it. Based on various sensor inputs, the powertrain control module (PCM) adjusts engine idle speed by moving the IAC motor pintle in and out of the air control passage. The IAC motor is positioned when the ignition key is turned to the On position.

    A (factory adjusted) set screw is used to mechanically limit the position of the throttle body throttle plate. Never attempt to adjust the engine idle speed using this screw. All idle speed functions are controlled by the PCM.

    The idle air control motor is mounted to the throttle body adjacent to the throttle position sensor.

    IDLE AIR CONTROL (IAC) MOTOR TEST:
    To perform a complete test of IAC motor and its circuitry, refer to DRB scan tool and appropriate Powertrain Diagnostics Procedures manual. To test the IAC motor only, special IAC motor exerciser tool number 7558 may be used.

    CAUTION: Proper safety precautions must be taken when testing the IAC motor
    * Set the parking brake and block the drive wheels
    * Route all tester cables away from the cooling fans, drive belt, pulleys and exhaust components
    * Provide proper ventilation while operating the engine
    * Always return the engine idle speed to normal before disconnecting the exerciser tool
    (1) With the ignition OFF, disconnect the IAC motor wire connector at throttle body.
    (2) Plug the exerciser tool (7558) harness connector into the IAC motor.
    (3) Connect the red clip of exerciser tool (7558) to battery positive terminal. Connect the black clip to negative battery terminal. The red lamp on the exerciser tool will be illuminated when the exerciser is properly connected to battery.
    (4) Start engine. When the switch is in the HIGH or LOW position, the lamp on the exerciser tool will flash. This indicates that voltage pulses are being sent to the IAC stepper motor.
    (5) Move the switch to the HIGH position. The engine speed should increase. Move the switch to the LOW position. The engine speed should decrease.
    (a) If the engine speed changes while using the exerciser tool, the IAC motor is functioning properly. Disconnect the exerciser tool and connect the IAC stepper motor wire connector to the stepper motor.
    (b) If the engine speed does not change, turn the ignition OFF and proceed to step (6). Do not disconnect exerciser from the IAC stepper motor.
    (6) Remove the IAC stepper motor from the throttle body.
    [/b]CAUTION: When checking IAC motor operation with the motor removed from the throttle body, do not extend the pintle more than 6.35 mm (.250in).[/b]
    If the pintle is extended more than this amount, it may separate from the IAC stepper motor. The IAC motor must be replaced if the pintle separates from the motor.

    [/b]IAC Motor Testing[/b]
    (7) With the ignition OFF, cycle the exerciser tool switch between the HIGH and LOW positions. Observe the pintle. The pintle should move in-and-out of the motor.
    (a) If the pintle does not move, replace the IAC motor. Start the engine and test the replacement motor operation as described in step (5).
    (b) If the pintle operates properly, check the IAC motor bore in the throttle body bore for blockage and clean as necessary. Install the IAC motor and retest. If blockage is not found, refer to the DRB scan tool and the appropriate Powertrain Diagnostics Procedures service manual.

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INTAKE AIR TEMPERATURE SENSOR
  • The intake manifold air temperature sensor is installed into the intake manifold plenum.

    The intake manifold air temperature sensor is installed in the intake manifold with the sensor element extending into the air stream (Fig. 4). The
    sensor provides an input voltage to the powertrain control module (PCM) indicating intake manifold air temperature. The input is used along with inputs from other sensors to determine injector pulse width. As the temperature of the air-fuel stream in the manifold varies, the sensor resistance changes. This results in a different input voltage to the PCM.

    REMOVAL—4.0L 6 CYLINDER ENGINE
    The intake manifold air temperature sensor is installed into the intake manifold plenum on the 4.0L engine.
    (1) Disconnect the electrical connector from the sensor.
    (2) Remove the sensor from the intake manifold.

    INSTALLATION—4.0L ENGINE
    (1) Install the air temperature sensor into the intake manifold. Tighten the sensor to 13 Nzm (10 ft. lbs.) torque.
    (2) Connect the electrical connector to the sensor.

    REMOVAL—5.2L V-8 ENGINE
    The air temperature sensor is located in right-front side of intake manifold on the 5.2L engine.
    (1) Disconnect electrical connector at sensor.
    (2) Remove sensor from intake manifold.

    INSTALLATION—5.2L ENGINE
    (1) Install sensor to intake manifold. Tighten the sensor to 13 Nzm (10 ft. lbs.) torque.
    (2) Install electrical connector.

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MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR
  • The MAP sensor reacts to absolute pressure in the intake manifold and provides an input voltage to the powertrain control module (PCM). As engine load changes, manifold pressure varies, causing the MAP sensor voltage to change. This change results in a different input voltage to the PCM. The input voltage level supplies the PCM with information. This relates to ambient barometric pressure during engine start-up (cranking) and to engine load while the engine is running. The PCM uses this input, along with inputs from other sensors, to adjust air-fuel mixture.

    For more information, refer to Group 14, Fuel System. On 4.0L 6 cylinder engines, the MAP sensor is mounted on the dash panel. It is connected to the throttle body with a vacuum hose and to the PCM electrically.

    On 5.2L V-8 engines, the MAP sensor is mounted to the throttle body. It is connected to the throttle body with an L-shaped rubber fitting and to the PCM electrically.

    REMOVAL—4.0L 6 CYLINDER ENGINE
    The sensor is located on the cowl panel near the rear of the engine valve cover if equipped with the 4.0L engine.
    (1) Disconnect the sensor electrical connector.
    (2) Disconnect the sensor vacuum supply hose.
    (3) Remove the two sensor mounting bolts and remove sensor from vehicle.

    INSTALLATION—4.0L ENGINE
    (1) Install sensor to cowl panel. Install 2 screws and tighten to 3 Nzm (25 in. lbs.) torque.
    (2) Install the sensor vacuum supply hose.
    (3) Connect the sensor electrical connector.

    REMOVAL—5.2L V-8 ENGINE
    The MAP sensor is located on the front of the throttle body if equipped with the 5.2L engine. An L-shaped rubber fitting is used to connect the MAP sensor to throttle body. The throttle body must be removed from the intake manifold for MAP sensor removal.
    (1) Remove air intake tube at throttle body.
    (2) Remove throttle body. Refer to Throttle Body removal in the Group 14, Fuel System section of this manual.
    (3) Remove two MAP sensor mounting bolts.
    (4) While removing MAP sensor, slide the L-shaped rubber vacuum fitting from the throttle body.
    (5) Remove rubber fitting from MAP sensor.

    INSTALLATION—5.2L ENGINE
    (1) Install L-shaped rubber fitting to MAP sensor.
    (2) Position MAP sensor to throttle body while guiding L-shaped rubber fitting over throttle body fitting.
    (3) Install MAP sensor mounting bolts. Tighten bolts to 3 Nzm (25 in. lbs.) torque.
    (4) Install throttle body. Refer to Throttle Body installation in the Group 14, Fuel System section of this manual.
    (5) Install air intake tube.

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OXYGEN (O2S) SENSOR—PCM INPUT
  • The O2S sensor is located in the exhaust down pipe. It provides an input voltage to the powertrain control module (PCM) relating the oxygen content of the exhaust gas. The PCM uses this information to fine tune the air-fuel ratio by adjusting injector pulse width. The O2S sensor produces voltages from 0 to 1 volt. This voltage will depend upon the oxygen content of the exhaust gas in the exhaust manifold. When a large amount of oxygen is present (caused by a lean air-fuel mixture), the sensor produces a low voltage. When there is a lesser amount present (rich air-fuel mixture) it produces a higher voltage. By monitoring the oxygen content and converting it to electrical voltage, the sensor acts as a rich-lean switch. The oxygen sensor is equipped with a heating element
    that keeps the sensor at proper operating temperature during all operating modes. Maintaining correct sensor temperature at all times allows the
    system to enter into closed loop operation sooner. In Closed Loop operation, the powertrain control module (PCM) monitors the O2S sensor input (along with other inputs). It then adjusts the injector pulse width accordingly. During Open Loop operation, the PCM ignores the O2S sensor input and adjusts injector pulse width to a preprogrammed value (based on other sensor inputs).

    The O2S sensor is installed in the exhaust down pipe just below the exhaust manifold flange.

    WARNING: THE EXHAUST MANIFOLD BECOMES VERY HOT DURING ENGINE OPERATION. ALLOW ENGINE TO COOL BEFORE REMOVING OXYGEN SENSOR.

    REMOVAL
    (1) Raise and support the vehicle.
    (2) The sensors electrical connector clip is pushed over an oil pan mounting stud. Pull the connector clip from the mounting stud.
    (3) Separate the electrical connectors.
    (4) Remove the O2S sensor from the exhaust manifold. Snap-On oxygen sensor wrench (number YA 8875) may be used for removal and installation.

    INSTALLATION
    Threads of new factory oxygen sensors are coated with anti-seize compound to aid in removal.
    (1) Install the O2S sensor into the exhaust manifold and tighten to 30 Nzm (22 ft. lbs.) torque.
    (2) Connect the O2S sensor wire connector to the main harness.
    (3) Push the sensor clip on firmly at the oil pan stud.
    (4) Lower the vehicle.

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THROTTLE POSITION SENSOR (TPS)
  • The sensor is mounted on the throttle body. It is connected to the throttle blade shaft. The sensor is a variable resistor. It provides the powertrain control module (PCM) with an input signal (voltage) that represents throttle blade position. As the position of the throttle blade changes, the resistance of the sensor changes.

    The PCM supplies approximately 5 volts to the sensor. The sensor output voltage (input signal to the PCM) represents the throttle blade position. The PCM receives an input signal voltage from the sensor. This will vary in an approximate range of from 1 volt at minimum throttle opening (idle), to 4 volts at wide open throttle. Along with inputs from other sensors, the PCM uses the sensor input to determine current engine operating conditions. It also will adjust fuel injector pulse width and ignition timing.

    For component testing, refer to the Diagnostics/Service Procedures section of this group. For removal and installation of this component, refer to the Component Removal/Installation section of this group.

    THROTTLE POSITION SENSOR TEST
    To perform a complete test of this sensor and its circuitry, refer to the DRB scan tool. Also refer to the appropriate Powertrain Diagnostics Procedures manual. To test the sensor only, refer to the following: The throttle position sensor can be tested with a digital voltmeter. The center terminal of the sensor connector is the output terminal.

    With the ignition key in the ON position and engine not running, check the sensor output voltage at the center terminal wire of the connector. Check this at idle (throttle plate closed) and at wide open throttle (WOT). At idle, sensor output voltage should be greater than 200 millivolts. At wide open throttle, sensor output voltage must be less than 4.8 volts. The output voltage should increase gradually as the throttle plate is slowly opened from idle to WOT.

    REMOVAL—4.0L 6 CYLINDER ENGINE
    The throttle position sensor is mounted to the throttle body on the 4.0L engine.
    (1) Disconnect sensor electrical connector.
    (2) Remove the two sensor mounting bolts.
    (3) Remove sensor.

    INSTALLATION—4.0L ENGINE
    The throttle shaft end slides into a socket in the sensor. The sensor must be installed so that it can be rotated a few degrees. (If the sensor will not rotate, install the sensor with the throttle shaft on the other side of the socket tangs). The sensor will be under slight tension when rotated.
    (1) Install the throttle position sensor and two retaining bolts.
    (2) Connect sensor electrical connector to sensor.
    (3) Operate the throttle by hand to check for binding.

    REMOVAL—5.2L V-8 ENGINE
    The TPS is located on the side of the throttle body on the 5.2L engine.
    (1) Remove air intake tube at throttle body.
    (2) Disconnect TPS electrical connector.
    (3) Remove two TPS mounting bolts.
    (4) Remove TPS from throttle body.

    INSTALLATION—5.2L ENGINE
    The throttle shaft end of the throttle body slides into a socket in the TPS. The TPS must be installed so that it can be rotated a few degrees. If
    the sensor will not rotate, install the sensor with the throttle shaft on the other side of the socket tangs. The TPS will be under slight tension when rotated.
    (1) Install the TPS and two retaining bolts.
    (2) Tighten bolts to 7 Nzm (60 in. lbs.) torque.
    (3) Manually operate the throttle control lever by hand to check for any binding of the TPS.
    (4) Connect TPS electrical connector to TPS.
    (5) Install air intake tube.

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Old 07-09-2007, 01:13 PM   #2
Angelous
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I dont see a copy write infringement here.
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Old 07-09-2007, 01:29 PM   #3
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:mrgreen: Whatchu talkin' bout willis?
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Old 07-09-2007, 01:37 PM   #4
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:lol: :lol:
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Old 07-09-2007, 09:24 PM   #5
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Cheater, i did mine from memory. :angry: :mrgreen:
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Old 07-09-2007, 09:33 PM   #6
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haha I threw in some of your info too.
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Old 07-28-2007, 06:49 PM   #7
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[smilie=bal_ask.gif] Right now my 94 zj is d.i.d. (dead in driveway) a cheapo tester showed i had no spark on my plug wires or my coil wire so i put a volt meter in the connector that goesto the ignition coil and it showed battery voltage only momentarily when the system was first tried to start after that it went dead (no voltage) do you guys think this could possibly be a bad crankshaft sensor? it would be nice if it was not a problem with the PCM
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Old 10-29-2011, 06:29 PM   #8
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I'm laughing my A$$ off right now. "When removing the connector from sensor, do not pull directly on wiring harness. Fabricate an L-shaped hook tool from a coat hanger (approximately eight inches long)." Definitely from an official Chrysler dealer service manual... They WOULD have you make a tool from a COAT HANGER while the vehicle is on the lift at "So-and-So Chrysler", and you have 45 minutes to get it done... I love these people...
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