What is the Manifold Temperature Sensor all about?

Air is the single most important element for a running engine, even more so than fuel or oil. Without a flow of fresh, clean air, combustion cannot take place, and your engine cannot operate. However, simply ensuring that airflow can reach the intake is not enough. The car’s computer needs to know a lot of information about the temperature and quality of air entering the intake. The manifold temp sensor is responsible for determining the temperature of the air, and providing that information to the computer.

The computer will determine the density of the air and adjust the fuel flow to meet that. Depending on the make and model you drive, your car may have more than one manifold temp sensor. For instance, if you have a split manifold, you’ll have a sensor for each part. Like all other sensors on your car, the manifold temp sensor is subject to high heat and wear and tear. Electrical problems such as shorts and broken wires augment the list of potential troubles.

Keep in mind:

• The manifold temp sensor is not part of any maintenance inspection.
• The sensor can fail due to damage to the sensor or the wiring harness.
• A failed sensor will activate your Check Engine light.

How it's done:

• The air cleaner is removed for access
• The defective manifold temperature sensor is removed
• The new manifold temperature is installed and connected
• The air cleaner assembly is reinstalled
• The vehicle is started and checked for coolant leaks and sensor operation

Our recommendation:

Your manifold temp sensor is subject to considerable temperature extremes and will eventually fail. Without this component and the information it provides, the computer cannot determine the density of air entering the intake, resulting in an imbalanced air/fuel mixture. This causes rich or lean operation; both circumstances will damage the engine. If you suspect a problem with the manifold temperature sensor or experience the symptoms, have one of our expert mechanics diagnose the sensor.

What common symptoms indicate you may need to replace the Manifold Temperature Sensor?

• Check Engine light is on
• Erratic engine operation due to incorrect air/fuel ratio

How important is this service?

Having an operational manifold temp sensor is critical for vehicle operation. If your Check Engine light is on, or you experience fuel or acceleration related problems, this may be the cause. Because many other problems display similar symptoms, it is important to work with our expert mechanics to diagnose the actual issue and make the necessary repairs.