GM GENUINE PARTS Engine Coolant Temperature Sensor 213-4777 — OE-fit direct replacement, restores accurate temp

GM Genuine Parts 213-4777 (12639899) is an original-equipment engine coolant temperature sensor built to restore accurate engine temperature readings and OE-level fitment for compatible GM vehicles.

This engine coolant temperature (ECT) sensor from GM Genuine Parts (also referenced as ACDelco GM Original Equipment) replaces the factory sensor and delivers the signal the engine control module (ECM) needs to manage air/fuel mixture and ignition timing. Designed and manufactured to meet GM specifications, the 213-4777 sensor offers the same mechanical dimensions, electrical characteristics, and service life expected from factory components, so you can fit it without modification and rely on consistent engine performance.

How does this sensor affect my vehicle's operation?

The ECT sensor provides real-time temperature data to the ECM, which uses that information to optimize fuel delivery and ignition timing. If the sensor reads incorrectly, the engine may run too rich or too lean, and drivability or emissions can be affected. Replacing a faulty sensor with this GM OE part helps restore proper engine control and prevents diagnostic trouble codes related to temperature sensing.

• Direct replacement for the factory sensor on compatible GM models
• Restores accurate temperature input to the ECM for fuel/ignition adjustments
• Prevents temperature-related diagnostic trouble codes and limp-home behavior

What makes GM Genuine Parts 213-4777 an OE-quality option?

This sensor is manufactured to GM original-equipment specifications for fit, form, and function, meaning threading, connector type, and electrical response match the factory unit. Quality control and materials selection follow GM standards, so the part performs and lasts like the component it replaces. That consistency reduces the risk of premature failure and the need for repeat repairs.

• Built to GM OE specifications for dimensional and electrical compatibility
• Materials and assembly consistent with factory durability expectations
• Designed to integrate seamlessly with original wiring harness and mounts

How do I install this replacement temperature sensor?

Installation is typically straightforward for anyone comfortable with light engine work: drain coolant as needed, unplug the sensor connector, remove the old sensor, and install the GM sensor with proper thread sealant or gasket if required. Torque to the vehicle manufacturer’s specification and refill coolant, then clear any stored codes and run the engine to confirm correct operation. If you’re unsure, a professional technician or service manual will provide vehicle-specific steps and torque values.

• Disconnect battery and relieve system pressure before beginning
• Drain coolant sufficiently to prevent spillage when removing the sensor
• Use correct sealing method and torque per vehicle service specifications

Will this sensor work with my GM vehicle model and year?

The 213-4777 (12639899) is a GM-recommended replacement that fits specific GM applications. Confirm fitment by checking your vehicle’s VIN, existing part number, or an official parts lookup to ensure compatibility. Using the exact OE part number prevents electrical mismatches and ensures the connector, thread, and temperature curve align with the ECM’s expectations.

• Match part number 213-4777 / 12639899 to your vehicle before ordering
• Verify connector type and thread size against the original sensor
• Use VIN or dealer parts lookup for precise compatibility confirmation

Who is this for? The GM Genuine Parts 213-4777 (12639899) ECT sensor is intended for GM owners, DIY mechanics, and professional technicians seeking a factory-equivalent replacement for a failing or outdated engine coolant temperature sensor. It’s ideal when you want guaranteed fitment, reliable temperature input for the ECM, and the durability associated with GM original-equipment components. If your vehicle shows temperature-related trouble codes, poor warm-up behavior, or inconsistent idling linked to temperature sensing, this GM OE sensor is a direct, specification-matched solution.

• GM-recommended replacement part for your GM vehicle’s original factory component
• Offering the quality, reliability, and durability of GM OE
• Manufactured to GM OE specification for fit, form, and function