Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1988 Merkur Scorpio AutomaticFACTORY OEM SERVICE PROCEDURE
EEC-IV System
- Description & Operation
- Notes
- Input Devices
- A/C Compressor Clutch Signal
- Air Charge Temperature (ACT) Sensor
- EEC-IV Power Relay
- Engine Coolant Temperature (ECT) Sensor
- Heated Exhaust Gas Oxygen (HEGO) Sensor
- Manifold Absolute Pressure (MAP) Sensor
- Pressure Feedback Electronic (PFE) EGR valve
- Profile Ignition Pick-Up (PIP)
- Self-Test Input (STI)
- Throttle Position Sensor (TPS)
- Vehicle Speed Sensor (VSS)
- ECA Output Controlled Devices
- Diagnosis & Testing
- Quick Test
- Diagnosis By Symptom Test
- Circuit Tests
- How To Use Circuit Test
- Test A - No Start
- Test B - Vehicle Battery
- Test C - Reference Voltage
- Test Db - Air Charge Temperature (Act) Sensor
- Test De - ECT Sensor
- Test DF - Map/BP Sensor
- Test DH - TPS
- Test DL - PFE & EVR
- Test Fa - Neutral Switch
- Test Hg - Fuel Control
- Test J - Inertia Switch
- Test KD - CANP Check
- Test KE - ISC Air By-Pass
- Test M - Dynamic Response
- Test P - Timing Check
- Test Q1 - No Codes/Codes Not Listed
- Test Q2 - Code 15 KOEO
- Test Q3 - Output Check
- Test Q4 - ECA Power Check
- Test S - System Check
- Test X - Wot/WAC Switch
- Test Y - Erratic Ignition
- Test Z - Air Management
Factory Service Tools
Use the Manual With the Right Hardware
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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.