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.
2011 Ford Fiesta L4-1.6LFACTORY OEM SERVICE PROCEDURE
Catalyst Monitor Sensor (CMS)
Engine Control Components - Exploded View
Catalyst Monitor Sensor (CMS)
NOTE: If necessary, lubricate the CMS with penetrating and lock lubricant to assist in removal.
NOTE: Apply anti-seize to the threads of the CMS prior to installing.
NOTE: The correct torque wrench setting must be calculated when using a commercially available exhaust gas sensor socket to install the CMS.
1. Refer to the procedures and/or exploded views for any Warnings, Notices, Notes, Materials, Specifications, and Special Tools. Items in the exploded views may not be listed in order of removal.
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.
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