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.
Test S - Introduction
Perform this test only after Code 11 is displayed in KOEO Self-Test and you have been directed here from TEST A, step 20) or by a driveability symptom.
- ISC by-pass air system
- MAP system
- EGR system
- MAP system
To prevent the replacement of good components, be aware that the following non-EEC-IV areas may be at fault:
- Faulty power or ground connections
- Ignition system (distributor cap, rotor, wires, coil, plugs)
- Basic mechanical engine components (cam timing, compression, etc.)
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.
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