Wrangler L4-150 2.5L VIN P MFI (1993)
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Throttle Position Sensor (TPS)
Based On These Inputs The PCM Will:
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Adjust engine idle speed through the IAC motor.
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Adjust ignition timing.
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Operate A/C Compressor Clutch relay (if selected).
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Ignore oxygen sensor input. The PCM will enter fuel cut-off strategy (under hard deceleration).
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Determine proper injector pulse width and continue injection (under normal deceleration).
Engine Start-Up
THIS IS AN OPEN LOOP MODE.
When the starter motor is engaged, the Powertrain Control Module (PCM) receives input from:
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Battery voltage
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Crankshaft position (CKP) sensor
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Engine coolant temperature (ECT) sensor
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Intake air temperature (IAT) sensor
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Throttle position sensor (TPS)
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Camshaft position (CMP) sensor
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Starter relay
Based on these inputs the PCM will:
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Monitor crankshaft and camshaft position sensor. If signals are not received within 1 second, the PCM will shut down the Automatic Shutdown
(ASD) and fuel pump relays.
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Supply the injectors with a ground path, firing all injectors until the PCM determines crankshaft position.
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Fire injectors in sequence, once PCM has determined crankshaft position.
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Compare RPM Manifold Absolute Pressure (MAP) sensor reading to idle speed MAP sensor reading. If the PCM does not detect a minimum
difference it will set a Diagnostic Trouble Code.
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Determine proper ignition timing.
Engine Warm-Up
THIS IS AN OPEN LOOP MODE.
During engine warm-up, the Powertrain Control Module (PCM) receives input from:
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Battery voltage
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Crankshaft position (CKP) sensor
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Engine coolant temperature (ECT) sensor
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Intake air temperature (IAT) sensor
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Manifold absolute pressure (MAP) sensor
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Throttle position sensor (TPS)
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Camshaft position (CMP) sensor
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A/C select switch (if equipped)
Based on these inputs the PCM will:
