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Jeep
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2025
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Grand Cherokee 4xe
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Repair and Diagnosis
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Engine Performance
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System
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2.0L - DTCS P0128 To P0140
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DTC Troubleshooting
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P0139 O2 Sensor 1/2 Slow Response
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Set Condition
Set Condition
The Powertrain Control Module (PCM) does not detect a rich to lean switch within a calibrated time during a decel fuel shutoff event.