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.
2008 Ford Focus L4-2.0LFACTORY OEM SERVICE PROCEDURE
Catalyst Monitor Sensor
CATALYST MONITOR SENSOR
Exploded View
Special Tool(s)
Removal and Installation
1. With the vehicle in NEUTRAL, position it on a hoist.
2. Disconnect the electrical connector and detach the wiring retainer.
3. NOTE: If necessary, lubricate the catalyst monitor sensor with penetrating and lock lubricant to assist in removal.
Using the special tool, remove the catalyst monitor sensor.
- To install, tighten to 48 Nm (35 lb-ft).
4. CAUTION: Make sure that the sensor wiring is routed away from hot surfaces and sharp edges or damage to the wiring may occur.
NOTE:
- Apply a light coat of anti-seize lubricant to the threads of the catalyst monitor sensor.
- Make sure that the electrical connector locking tab is engaged.
To install, reverse the removal procedure.
Exploded View
Special Tool(s)
Special Tool(s):
Removal and Installation
1. With the vehicle in NEUTRAL, position it on a hoist.
2. Disconnect the electrical connector and detach the wiring retainer.
3. NOTE: If necessary, lubricate the catalyst monitor sensor with penetrating and lock lubricant to assist in removal.
Using the special tool, remove the catalyst monitor sensor.
- To install, tighten to 48 Nm (35 lb-ft).
4. CAUTION: Make sure that the sensor wiring is routed away from hot surfaces and sharp edges or damage to the wiring may occur.
NOTE:
- Apply a light coat of anti-seize lubricant to the threads of the catalyst monitor sensor.
- Make sure that the electrical connector locking tab is engaged.
To install, reverse the removal procedure.
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.
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