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.
1986 Merkur XR4Ti AutomaticFACTORY OEM SERVICE PROCEDURE
Idle Speed Controller
- Check wiring and controller for damage or deterioration. If okay, go to step 2). If wiring is defective, repair as necessary.
- Connect test light to idle speed actuator between Red wire and chassis ground. Turn ignition to "RUN" position. If light is on. go to step 3). If light is off, repair open in power feed circuit.
- With test light connected, connect jumper wire from actuator Gray wire to a chassis ground and turn ignition to "RUN position. If test light is on , go to step 4) If test light is off, replace idle speed controller.
- Using an ohmmeter check for continuity between wire at EEC pin No. 21 and Gray wire at controller. If continuity, is present, and repeat IDLE SPEED CONTROLLER test.
Factory Service Tools
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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.