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4.2L Engine Diagnostic Tests

Fig 1: Diagnostic Test No. 1 - Operational Test

G90D15852

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Fig 2: Diagnostic Test No. 1 - Operational Test (Cont.)

G90E15853

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Fig 3: Diagnostic Test No. 2 - Initialization Test (1 of 3)

G90F15854

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Fig 4: Diagnostic Test No. 2 - Initialization Test (2 of 3)

G90G15855

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Fig 5: Diagnostic Test No. 2 - Initialization Test (3 of 3)

G90H15856

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Fig 6: Diagnostic Test No. 3 - Open Loop Switch Test (1 of 5)

G90I15857

Courtesy of CHRYSLER MOTORS.

Fig 7: Diagnostic Test No. 3 - Open Loop Switch Test (2 of 5)

G90J15858

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Fig 8: Diagnostic Test No. 3 - Open Loop Switch Test (3 of 5)

G90A15859

Courtesy of CHRYSLER MOTORS.

Fig 9: Diagnostic Test No. 3 - Open Loop Switch Test (4 of 5)

G90D15860

Courtesy of CHRYSLER MOTORS.

Fig 10: Diagnostic Test No. 3 - Open Loop Switch Test (5 of 5)

G90I15873

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Fig 11: Diagnostic Test No. 4 - Closed Loop Test

G90E15861

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Fig 12: Diagnostic Test No. 5 - Electronic Ignition Retard Test

G90F15862

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NOTE: For additional oxygen sensor information, see TITANIA OXYGEN SENSOR TESTING article.

Fig 13: Diagnostic Test No. 6 - Oxy Sens & Closed Loop Test (1 of 2)

G90G15863

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NOTE: For additional oxygen sensor information, see TITANIA OXYGEN SENSOR TESTING article.

Fig 14: Diagnostic Test No. 6 - Oxy Sens & Closed Loop Test (2 of 2)

G90H15864

Courtesy of CHRYSLER MOTORS.

Fig 15: Diagnostic Test No. 7 - Downstream Solenoid Test (1 of 2)

G90I15865

Courtesy of CHRYSLER MOTORS.

Fig 16: Diagnostic Test No. 7 - Downstream Solenoid Test (2 of 2)

G90J15866

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Fig 17: Diagnostic Test No. 8 - Upstream Solenoid Test (1 of 2)

G90A15867

Courtesy of CHRYSLER MOTORS.

Fig 18: Diagnostic Test No. 8 - Upstream Solenoid Test (2 of 2)

G90B15868

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Fig 19: Diagnostic Test No. 9 - Idle Speed Control System Test

G90C15869

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Fig 20: Diagnostic Test No. 10 - Sole-Vac Vacuum Switch Sol Test

G90F15870

Courtesy of CHRYSLER MOTORS.

Fig 21: Diagnostic Test No. 11 - Sole-Vac Idle Speed Relay Test

G90G15871

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Fig 22: Basic Engine Test

G90H15872

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