2006 Ford F150 P0198 Engine Oil Temp Sensor

2006 Ford F150


  • 5.4L Triton V8
  • Horsepower: Approximately 300 hp @ 5,000 rpm
  • Torque: Approximately 365 lb-ft @ 3,750 rpm


  • 4-speed automatic transmission

Fuel Economy:

  • City: Approximately 13 mpg
  • Highway: Approximately 17 mpg

Understanding and Diagnosing P0198 Code in a 2006 Ford F150 with the 5.4L Engine

The 2006 Ford F150 equipped with the 5.4L engine is a reliable workhorse, but like any vehicle, it may experience occasional issues. One common problem that owners may encounter is the P0198 trouble code. In this article, we’ll delve into what this code means, its possible causes, symptoms, and how to diagnose and address the issue.

What is the P0198 Code?

The P0198 code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various components and systems in a vehicle. Specifically, P0198 relates to the Engine Oil Temperature (EOT) sensor circuit having a high voltage input. This sensor is crucial for maintaining optimal engine performance and preventing overheating.


Symptoms of P0198 Code:

  1. Check Engine Light (CEL): The most obvious sign is the illumination of the check engine light on the dashboard.
  2. Poor Engine Performance: The vehicle may experience a decrease in power and overall performance.
  3. Overheating: If the engine oil temperature sensor is not functioning correctly, it may not provide accurate temperature readings, leading to potential engine overheating.

Possible Causes:

  • Faulty EOT Sensor: The engine oil temp sensor itself may be malfunctioning, providing incorrect voltage readings.
engine oil temp sensor

The engine oil temp sensor is a crucial component in a vehicle’s engine management system, responsible for monitoring the temperature of the engine oil.

  • Wiring Issues: Damaged or corroded wiring in the engine oil temp sensor circuit can lead to high voltage input.
  • Connector Problems: Poor connections or loose connectors can disrupt the sensor’s signal.
  • Engine Coolant Temperature (ECT) Sensor Malfunction: As the ECT and EOT sensors are interconnected, a problem with the ECT sensor can trigger the P0198 code.

Diagnosing and Fixing the Issue:

  1. Scan for Codes: Use an OBD-II scanner to retrieve the trouble codes. P0198 will indicate the issue with the engine oil temp sensor.
  2. Inspect Wiring and Connectors: Check the wiring and connectors for any signs of damage, corrosion, or loose connections.
  3. Test EOT Sensor: Measure the voltage output of the EOT sensor using a multimeter. If it deviates from the specified range, consider replacing the sensor.
  4. Check ECT Sensor: Ensure that the Engine Coolant Temperature sensor is functioning correctly, as it can impact the EOT sensor’s readings.
  5. Clear Codes: After addressing the issue, clear the trouble codes using the OBD-II scanner.
  6. Monitor Vehicle: Drive the vehicle and monitor for any recurrence of the P0198 code. If the issue persists, further diagnostics may be necessary.


The P0198 code on a 2006 Ford F150 with the 5.4L engine requires prompt attention to prevent potential engine damage and ensure optimal performance. By understanding the symptoms and following a diagnostic approach, owners can address the issue and keep their vehicles running smoothly. If uncertain or uncomfortable with the diagnosis and repair process, consulting a professional Ford mechanic is always a wise decision.

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