Ford Focus Cylinder Head Temperature (CHT) Sensor Guide: 2014-2018
Is your 2014-2018 Ford Focus running rough or showing an overheat warning? The CHT sensor could be the culprit.
- A failing CHT sensor can trigger a P1299 code, which puts the car in a protective limp mode; do not ignore this warning.
- For this specific part, using the OEM Motorcraft sensor (Part # 8S4Z-6G004-A) is strongly recommended to ensure accurate readings and proper fit.
- DIY replacement is possible but requires a special extra-deep 19mm socket to remove and install the sensor.
- There are no specific recalls for this sensor, so repair will be at the owner's expense.
Is Your Focus CHT Sensor Failing?
A bad Cylinder Head Temperature (CHT) sensor can cause confusing symptoms. Because it provides critical temperature data to the engine computer, a failure can make your car run poorly or even trigger a fail-safe mode to protect the engine. Spotting the signs early can save you from a breakdown.
Common Symptoms of a Bad CHT Sensor:
- Check Engine Light: This is often the first sign. You may see codes like P1299 or P1289.
- Engine Overheating or Limp Mode: The P1299 code specifically means the computer has detected an overheat condition and may limit engine power to prevent damage.
- Fluctuating Temperature Gauge: The gauge on your dashboard might drop to cold and then shoot back up to normal or hot for no reason.
- Poor Engine Performance: Your car may run rough, hesitate, or have reduced fuel economy.
- A/C System Stops Working: The engine computer may shut down non-essential systems like the air conditioning when it detects an issue.
P1299 is a Serious Code
🎬 Watch: How to fix the P1299 overtemperature protection codeIf your car has a P1299 trouble code, it means the engine's computer believes the cylinder head is dangerously hot. The computer activates a "fail-safe" cooling strategy, which may involve shutting off fuel to some cylinders to air-cool them. You should not continue to drive the vehicle for long distances in this condition.
Choosing the Right Aftermarket Sensor
When it comes to this specific sensor for the 2014-2018 Focus, there is a strong case for using the original equipment (OEM) part from Ford/Motorcraft. However, several aftermarket options are available from brands like Dorman, Standard Ignition, and Motorad.
OEM vs. Aftermarket Quality
For many parts, aftermarket brands offer a great balance of quality and price. For this CHT sensor, however, mechanics and DIYers often report issues with aftermarket versions. Problems include incorrect fitment, different materials that affect heat reading, and inaccurate temperature signals sent to the computer. Multiple sources specifically recommend using the OEM sensor to avoid these problems. While some aftermarket brands like Standard Ignition (SMP) and NGK are reputable, the risk of a poor fit or incorrect reading makes the OEM Motorcraft sensor a safer bet for this critical component. Dorman parts have a mixed reputation in forums, with some users experiencing quality issues.
Pro Tip: Buy OEM for a Perfect Fit
Given the low cost of the OEM Motorcraft sensor and the potential for issues with aftermarket versions, spending a few extra dollars for the factory part is a wise investment. It ensures correct readings, proper fit, and reliable performance. The OEM part number is 8S4Z-6G004-A.
Cost of Replacing the CHT Sensor
The cost to replace the CHT sensor on a 2014-2018 Ford Focus is relatively low, but labor can vary depending on whether your mechanic has the required special tool.
| Part/Service | Estimated Cost |
|---|---|
| New OEM (Motorcraft) | $34 - $51 |
| New Aftermarket | $31 - $43 |
| Shop Labor | $100 - $200 |
| Total Estimated Cost | $134 - $251 |
Frequently Asked Questions (FAQ)
Is a CHT sensor the same as an ECT sensor?
No. An Engine Coolant Temperature (ECT) sensor measures the temperature of the coolant fluid. A Cylinder Head Temperature (CHT) sensor measures the temperature of the engine's metal head. For your Focus, the computer uses the CHT reading to calculate what the coolant temperature should be.
🎬 Learn the difference between CHT and ECT sensor locationsIs this a difficult DIY job?
The replacement itself is not complex, but it requires a special tool: an extra-deep 19mm socket to fit over the sensor's body. Without this specific socket, the job is nearly impossible. The sensor is located between the spark plugs on top of the engine. If you have the tool, it can be done in under an hour.
🎬 See this walkthrough for replacing the sensor yourselfAre there any recalls for this sensor?
No, there are no active recalls from Ford or NHTSA for a faulty CHT sensor on the 2014-2018 Ford Focus with the 2.0L engine. Recalls you may find for other Focus models or engines typically relate to other cooling system components.
What is the rubber boot on top of the sensor?
There is a rubber boot or grommet that covers the sensor and its connector. It's common for this boot to become brittle and break or pop off. Unfortunately, this part is often not sold separately from the larger engine wiring harness, making it difficult to find a replacement.
Helpful Videos
Technical Specifications
OEM Part Numbers: 8S4Z-6G004-A 7L5Z-6G004-A
Location: On cylinder head, between spark plug wells. Required Tool: Extra-deep 19mm socket.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Ford Focus:
- 🎬 Helpful Videos
- 🛍️ Shop This Part
- Is Your Focus CHT Sensor Failing?
- Common Symptoms of a Bad CHT Sensor:
- P1299 is a Serious Code
- Choosing the Right Aftermarket Sensor
- OEM vs. Aftermarket Quality
- Pro Tip: Buy OEM for a Perfect Fit
- Cost of Replacing the CHT Sensor
- Frequently Asked Questions (FAQ)
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