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HOMESERVICE MANUALSFORD1991RANGER 2D PICKUP, 4.0 X, 4WDREPAIR AND DIAGNOSISENGINE PERFORMANCESYSTEMENGINE CONTROLS - BASIC TESTING
1991 Ford Ranger 2D Pickup, 4.0 X, 4WD
Engine Controls - Basic Testing
1991 Ford Ranger 2D Pickup, 4.0 X, 4WDSECTION Engine Controls - Basic Testing
- Introduction
- Preliminary Inspection & Adjustments
- Compression
- Exhaust System BACKPRESSURE
- No-Start Diagnosis
- DISTRIBUTORLESS Ignition System (Dis) 2.3L
- Notes
- Test 1, Check ECA For Fault Codes
- Test 2, Check For Spark During Crank
- Test 3, Check Dis Module Pip Out
- Test 4, Check Pip Out Continuity
- Test 5, Determine Missing Spark Combination
- Test 6, Check Plugs & Wires
- Test 7, Check Dis Module VBAT
- Test 8, Check Dis Module Ignition Ground
- Test 9, Check Dis Module Mounting Screws
- Test 10, Check Right Coil Pack Circuits
- Test 11, Right Coil Pack Fault, Isolate Dis Module
- Test 12, Check Right Coil Pack VBAT
- Test 13, Check Right Coil Circuit
- Test 14, Check Pip D At Dis Module
- Test 15, Check Dis Module Coil Drivers
- Test 16, Check Right Coil Pack VBAT
- Test 17, Check Right Coil Circuit
- Test 18, Check Right Coil Circuit
- Test 19, Isolate Dis Module From Pip D
- Test 20, Check Crankshaft Sensor VBAT
- Test 21, Check Crankshaft Sensor Ignition Ground
- Test 22, Check Crankshaft Sensor Pip S
- Test 23, Check Pip Circuit For Short To Ground
- Test 24, Check Pip Circuit For Short To VBAT
- Test 25, Check Crankshaft Vane
- Test 26, Isolate EEC-IV Processor (ECA) From Pip Circuit
- Test 27, Check Pip EEC Circuit For Short To VBAT
- Test 28, Check Pip EEC Circuit For Short To Ground
- Electronic DISTRIBUTORLESS Ignition System (EDIS) 4.0L Engine
- Notes
- Test 1, Check ECA For Fault Codes
- Test 2, Check For Spark During Crank
- Test 3, Check Pip At EDIS Module
- Test 4, Check Pip Continuity To EEC
- Test 5, Check IGND At EDIS
- Test 6, Check IGND Continuity To EEC
- Test 7, Check Plugs & Wires
- Test 8, Isolate EDIS Module/Pip Fault
- Test 9, Check Pip Circuit For Short To Ground
- Test 10, Check Pip Circuit For Short To Power
- Test 11, Check PWR GND To EDIS Module
- Test 12, Check PERF. W/O EDIS Diagnostic Cable Installed
- Test 13, Check PWR GND To EDIS Module
- Test 14, Check For VBAT Open To EDIS Module
- Test 15, Check VRS+ Bias At EDIS Module
- Test 16, Check VRS Amplitude At EDIS Module
- Test 17, Check VRS+ Bias/Isolate VRS/Bias Fault
- Test 18, Check VRS+ High Or Low/Bias Fault
- Test 19, Check VRS+ Circuit For Short To Ground
- Test 20, Check VRS+ Circuit For Short To VBAT
- Test 21, Check VRS Bias
- Test 22, Check VRS High Or Low/Bias Fault
- Test 23, Check VRS Circuit For Short To Ground
- Test 24, Check VRS Circuit For Short To VBAT
- Test 25, Check VRS Amplitude At EDIS Module
- Test 26, Check VRS Resistance
- Test 27, Check VRS Air Gap & Trigger Wheel
- Test 28, Check VRS High Or Low Resistance
- Test 29, Check VRS+ Shorted To VRS
- Test 30, Check VRS+ For Open Circuit
- Test 31, Check VRS For Open Circuit
- Test 32, Check For IDM Short High
- Test 33, Check For IDM Open Circuit
- Test 34, Check IDM Output From EDIS Module
- Test 35, Check For IDM Short In ECA
- Test 36, Check For IDM Short To Ground In Harness
- Test 37, Check For IDM Short To VBAT In Harness
- Test 38, Check Base Timing
- Test 39, Check Advance Spark Angle
- Test 40, Check Saw At EDIS Module
- Test 41, Check Saw For Short In EDIS Module
- Test 42, Check For Saw Short To Ground In Harness
- Test 43, Check For Saw Short To VBAT In Harness
- Test 44, Check For Saw Open
- Test 45, Inspect VR Sensor & Trigger Wheel
- Test 46, Check VBAT Open To Coil
- Test 47, Verify Vehicle Operating Mode
- Test 48, Check C1, C2 & C3 At Coil Pack
- Test 49, Check C1, C2 & C3 At Coil Pack
- Test 50, Check C1, C2 & C3 At Coil Pack
- Test 51, Check C1, C2 & C3 At EDIS
- Test 52, Check C1, C2 & C3 At Coil Pack
- Test 53, Check C1, C2 & C3 At Coil Pack
- Test 54, Check C1, C2 & C3 Coil Primary
- Test 55, Check C1, C2 & C3 For Short To Ground
- Test 56, Check C1, C2 & C3 For Short To Ground
- Thick Film Ignition (TFI) IV
- Fuel System
- Idle Speed & Ignition Timing
- Throttle Position Sensor (TPS) Adjustment
- Fuel Injection Pump Lever (FIPL) Sensor Adjustment
- Summary
RENDER: 1.0x
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.