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.
1991 Ford Probe LX, AutomaticFACTORY OEM SERVICE PROCEDURE
Quick Test: Description
The following procedures are functional tests of EEC-IV system. There are 7 basic test steps. These test steps must be carefully followed in sequence, otherwise misdiagnosis or replacement of non-faulty components may result.
- Visual Check & Vehicle Preparation
- Equipment Hookup
- Key On Engine Off (KOEO) Self-Test
- Computed Timing Check
- Key On Engine Running (KOER) Self-Test
- Continuous Monitor Mode (Wiggle Test)
- Intermittents & Diagnosis By Symptom
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.