Engine Controls - Adjustments - 2.5L: Other Dodge Dakota WS

VALVE CLEARANCE

Note. All engines use hydraulic lifters. No adjustments are required.

IGNITION TIMING

Note. Always refer to Emission Control Label in engine compartment before attempting service. If manual and label differ, always use emission label specifications.

1. Ensure all lights and accessories are off. Place transmission is in Neutral or Park and set parking brake. If using magnetic timing light, insert pick-up probe into receptacle next to timing scale window. If using an inductive timing light, connect pick-up to No. 1 spark plug wire. Refer to equipment manufacturer's instructions for proper connection.
2. Turn selector switch to appropriate cylinder position. Connect Diagnostic Readout Box (DRB) to Data Link Connector (DLC). If not using a DRB, disconnect engine coolant temperature sensor connector. Start engine, and run until normal operating temperature is reached. Radiator cooling fan will come on and Malfunction Indicator Light (MIL) will come on, after temperature sensor is disconnected or DRB is activated.
3. Check timing through timing window in bellhousing. See IGNITION TIMING table. If timing is incorrect, loosen distributor hold-down bolt and turn housing until specified timing is obtained.
4. Recheck timing after tightening distributor hold-down bolt. Reconnect coolant temperature sensor connector. Erase any fault codes.

IGNITION TIMING

ELECTRONIC SPARK ADVANCE (Degrees BTDC @ RPM)

THROTTLE BODY MINIMUM AIRFLOW

1. Set parking brake and block front wheels. Warm engine in Park or Neutral until cooling fan cycles on and off at least once. Ensure all accessories are off. Remove air cleaner assembly and plug heated air door vacuum hose. On all models, connect timing light and tachometer. Disconnect engine coolant temperature sensor. Set basic timing to 10-14 degrees BTDC. Turn engine off and connect coolant temperature sensor.
2. Disconnect PCV hose from intake manifold. Attach Air Metering Fitting (6457) to intake manifold PCV nipple.
3. Connect DRB to DLC. Start engine and allow to idle for at least one minute. Using DRB, access MINIMUM AIRFLOW IDLE SPEED. When accessed, IAC motor will fully close, spark advance will become fixed, fuel delivery will not change, and engine RPM will be displayed on DRB.
4. Check engine idle speed on tachometer. See THROTTLE BODY MINIMUM AIRFLOW IDLE SPECIFICATIONS table. On 3.0L models, go to next step. If throttle body minimum airflow idle speed is not within specification, check for vacuum leaks. If there are no vacuum leaks, replace throttle body.
5. While holding throttle open, spray throttle body bore and manifold side of throttle with Mopar Parts Cleaner. Using a soft scuff pad, clean top and bottom of throttle body bore and edges, and manifold side of throttle blade.
6. Dry throttle body with compressed air and inspect for foreign material. Install throttle body to engine and retest throttle body minimum airflow idle speed. If minimum airflow idle speed is not within specification, problem is not caused by throttle body.

THROTTLE BODY MINIMUM AIRFLOW IDLE SPECIFICATIONS

THROTTLE POSITION SENSOR (TPS)

Note. Throttle Position Sensor (TPS) is not adjustable. Following procedures may be used to check TPS calibration. For complete testing of TPS, see TESTS W/CODES - 2.5L TBI article in the ENGINE PERFORMANCE section.

1. Remove air cleaner housing assembly. Turn ignition switch to ON position. DO NOT start engine. Using a DVOM, measure voltage at center terminal of TPS, with throttle valve in idle position fully closed against stop. Voltage should be within specification. See THROTTLE POSITION SENSOR VOLTAGE TEST table. If voltage is not within specification, replace TPS.
2. Slowly open throttle valve to Wide Open Throttle (WOT). TPS voltage should increase steadily to specification. If voltage does not increase steadily to specification, replace TPS.

THROTTLE POSITION SENSOR VOLTAGE TEST (1)