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Mercury Tracer Intake Air Temperature Sensor Guide (1991-1999)

Fix poor gas mileage and rough idling in your Tracer by understanding and replacing a faulty intake air temperature sensor.

3 minutes to read 1991-1999 Mercury Tracer
Difficulty
1/5
Est. Time
0.25 hrs
DIY Doable?
✅ Yes
Shop Labor
$50-$100
Used OEM Price
$10-$25
⚠️ Drivable, but... — Yes, you can drive the vehicle, but you will experience poor fuel economy and performance until the sensor is replaced.
Key Takeaways
  • A bad IAT sensor commonly causes a Check Engine Light, poor gas mileage, and rough running on a Tracer.
  • For this part and vehicle, a quality aftermarket sensor is a reliable and cost-effective alternative to expensive OEM parts.
  • Replacement is a very easy DIY job that most owners can complete in under 15 minutes with basic tools.
  • Always check the sensor's wiring and connector for damage or corrosion before buying a new part.
The Engine Intake Manifold Temperature Sensor, also called the Intake Air Temperature (IAT) sensor, acts like a thermometer for your Tracer's engine. It measures the temperature of the air going into the engine. The engine's computer uses this information to create the right mix of air and fuel for the best performance and gas mileage. When the air is cold, it's denser and needs more fuel. When the air is warm, it's less dense and needs less fuel. This small sensor helps your engine run efficiently in all weather conditions.

Symptoms of a Bad Intake Air Temperature Sensor

When the IAT sensor fails, it sends wrong information to the engine's computer. The computer might think the air is very cold when it's warm, or vice-versa. This confusion can cause several noticeable problems with how your Tracer drives.

  • Check Engine Light: This is often the first sign. The computer will store a trouble code like P0110, P0112, or P0113.
  • Poor Fuel Economy: If the computer thinks the air is always cold, it will inject too much fuel, wasting gas.
  • Rough Idle: Your engine might idle unevenly or feel shaky when you're stopped.
  • Engine Hesitation: You might feel a lag or sluggish response when you press the gas pedal.
  • Hard Starting: The car may be difficult to start, especially when the engine is cold, because the fuel mixture is wrong.

Choosing the Right Aftermarket Sensor

For a 1991-1999 Mercury Tracer, an original Motorcraft sensor can be hard to find or more expensive. Aftermarket sensors are a very practical and affordable choice for this repair. The technology in this sensor is simple, and quality aftermarket brands provide a reliable fix.

Brand TierOur Available BrandsGeneral Quality & Price
Premium Aftermarket Standard Ignition A well-known brand trusted by many mechanics. Offers good quality and reliability, often with a better warranty. A solid choice that balances cost and performance.
Standard / Economy True Tech These are budget-friendly options that get the job done. For a simple sensor like the IAT, an economy brand is a functional choice if keeping costs as low as possible is the main goal.

Pro Tip: Before replacing the sensor, check its electrical connector. A loose, dirty, or corroded connector can cause the same symptoms as a bad sensor. Cleaning the connection might fix your problem for free.

Cost to Replace a Mercury Tracer IAT Sensor

Replacing the IAT sensor is one of the more affordable repairs you can make. The part itself is not expensive, and labor is minimal if you take it to a shop.

Cost CategoryEstimated Price Range
New Aftermarket Part$15 - $30
Shop Labor$50 - $100
Total Professional Repair$65 - $130

Frequently Asked Questions

Where is the IAT sensor located on my 1991-1999 Mercury Tracer?

The IAT sensor is located in the engine's air intake system. Look for a small plastic sensor with a two-wire connector plugged into the flexible air duct between the air filter box and the engine's throttle body. It is usually just pushed into a rubber grommet or held by small screws.

Can I replace this sensor myself?

Yes, this is a great job for a beginner. It is typically very easy to access. You just need to unplug the electrical connector, pull or unscrew the old sensor, and pop the new one in. The entire job usually takes less than 15 minutes and requires no special tools.

Is an aftermarket sensor good enough for my Tracer?

Absolutely. For a straightforward part like an IAT sensor on this vehicle, a quality aftermarket brand like Standard Ignition offers performance and reliability that is perfectly adequate for a daily driver. Given the age of the vehicle, it is a very sensible and cost-effective choice.

What happens if I don't replace a bad IAT sensor?

Your car will still run, but it will have poor performance, bad gas mileage, and higher emissions. Over time, running with a very rich fuel mixture can potentially damage other components like the catalytic converter, which is a much more expensive repair.

Technical Specifications

OEM Part Numbers: F57Z12A697A F57Z12A697AA F57F12A697AA F57F12A697AB

The Intake Air Temperature sensor for the 1991-1999 Mercury Tracer is a two-terminal thermistor sensor that modifies a voltage signal based on air temperature.

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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.

Year Coverage
This article covers the Engine Intake Manifold Temperature Sensor for:
  • Mercury Tracer: 199119921993199419951996199719981999
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