Chrysler Front Wheel Drive Cars 4-CYL 1981-1995 Repair Information

Diagnosis and Testing

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To test the ignition system perform the test procedures in a particular sequence. Start with the secondary spark test, commence to the coil test (located under the coil procedures later in this section) and finally perform the failure-to-start test. Performing the tests in this order will narrow down the ignition system problem in the easiest manner.

SECONDARY SPARK TEST



See Figure 1


CAUTION
The Direct Ignition System generates approximately 40,000 volts. Personal injury could result from contact with this system.

Since there are 2 independent coils in the assembly, each coil must be checked individually. Cylinders 1 and 4, and 2 and 3 are grouped together.

  1. Remove the cable from the No. 1 spark plug, then insert a clean spark plug into the spark plug boot.
  2.  

Due to the high secondary voltage and risk of electrical shock, it is advisable to wrap a thick, dry cloth around the boot before grasping it.


WARNING
Spark plug wire damage may occur if the spark plug is moved more than1/4in. (6mm) away from the engine ground.

  1. Ground the plug to the engine (touch the spark plug metal body to the engine block or other piece of metal on the car).
  2.  
  3. Crank the engine and look for spark across the electrodes of the spark plug.
  4.  
  5. Repeat the test for the three remaining cylinders. If there is no spark during all cylinder tests, refer to the failure-to-start test. If one or more tests indicate irregular, weak or no spark, refer to the coil test.
  6.  



Click image to see an enlarged view

Fig. Fig. 1: Make sure to ground the spark plug against the engine block or cylinder head

FAILURE-TO-START TEST



See Figure 2

Before proceeding with this test, refer to the testing procedures for the ignition coil, located later in this section.

  1. Using a Digital Volt/Ohmmeter (DVOM) measure the voltage from the negative (-) battery terminal to the positive (+) battery terminal. The voltage should be at least 12.4 volts. This amount of voltage is necessary for an accurate inspection of the system.
  2.  
  3. Detach the ignition coil harness connector and attach the positive (+) lead of the DVOM to the B+ terminal of the harness connector. Connect the negative lead of the DVOM to a good ground.
  4.  



Click image to see an enlarged view

Fig. Fig. 2: Ignition coil wiring harness connector terminal identification

  1. Crank the engine over for approximately 5 seconds while monitoring the voltage at the B+ connector terminal.
    1. If the voltage remains near zero during the entire period of cranking, check the Auto Shutdown (ASD) relay and PCM; refer to Driveability & Emission Controls for more details regarding Diagnosis Read-out Boxes (DRB scan tools) and PCM diagnostics.
    2.  
    3. If the voltage is at near-battery voltage and drops to zero after 1-2 seconds of cranking, check the camshaft sensor, crankshaft sensor and their circuits. Refer to Driveability & Emission Controls for more information on testing the crankshaft and camshaft position sensors.
    4.  
    5. If the voltage remains at near-battery voltage during the entire 5 seconds, continue with the test.
    6.  

  2.  

The Powertrain Control Module (PCM) is mounted to the left-hand inner fender, next to the battery.

  1. Turn the ignition key OFF . Remove the PCM 60-way connector. Check the 60-way connector for any terminals loose from the connector.
  2.  

 
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