Haltech HT-010302 Coolant Temp Sensor Large Thread 3/8 NPT 18TPI Delphi Plug

Vehicle Fitment

• Universal - compatible with all Haltech ECU platforms including the Nexus S2, S3, R3, R5, Elite 550, 750, 1500, 2500, and plug-in ECU series
• Suitable for all engine configurations requiring coolant temperature monitoring via a standalone ECU
• Compatible with any thermostat housing, engine block, coolant pipe, or custom fitting with a 3/8 NPT 18TPI thread boss

Fitment Notes

• Thread size is 3/8 NPT 18TPI (large thread). This is the NPT counterpart to the HT-010300 (M12 x 1.5). Select based on the thread present in your cooling system housing or adapter fitting.
• 3/8 NPT is common in American domestic engines, custom aluminum thermostat housings, and many aftermarket coolant adapters.
• Maximum operating temperature is 127°C (260°F) - suitable for normal engine coolant operating ranges.
• Sensor type is NTC thermistor - natively calibrated in all Haltech ECU software.
• Includes matching Delphi plug and pins - no separate connector purchase required.

Features

• Measures engine coolant temperature (ECT) and delivers real-time data to the ECU for cold-start enrichment, warm-up fuel trims, idle speed management, and cooling fan activation.
• 3/8 NPT 18TPI large thread fits domestic engine blocks, aftermarket thermostat housings, and custom coolant fittings without adapters.
• Built to OEM specifications for reliable, consistent output across the full operating temperature range.
• NTC thermistor sensor type - natively calibrated in all Haltech ECU software for accurate readings straight from the box.
• Weatherproof Delphi connector ensures a secure, moisture-resistant connection in demanding engine bay environments.
• Compact brass construction designed to withstand high-pressure cooling system environments.
• Matching Delphi plug and pins included - ready to wire without sourcing additional connectors.
• Essential for accurate overtemperature protection, cooling fan relay control, and fuel trim compensation during warm-up.

Specifications

• Part Number: HT-010302
• Sensor Type: NTC Thermistor (Coolant Temperature)
• Thread Size: 3/8 NPT 18TPI (Large Thread)
• Maximum Operating Temperature: 127°C (260°F)
• Connector: Delphi (included with plug and pins)
• Application: Universal - Engine Coolant Temperature

Included Components

• 1x Haltech Coolant Temperature Sensor (3/8 NPT 18TPI large thread)
• 1x Matching Delphi plug with pins

Product Description

The Haltech HT-010302 is a universal coolant temperature (ECT) sensor with a 3/8 NPT 18TPI large thread, designed for use with all Haltech ECU platforms. It is the large-thread NPT counterpart to the HT-010300 (M12 x 1.5), making it the correct choice wherever an NPT thread boss is present - common in domestic engine blocks, aftermarket aluminum thermostat housings, custom coolant pipes, and a wide range of NPT-threaded cooling system adapters. The sensor provides accurate real-time coolant temperature data to the ECU, enabling cold-start enrichment, warm-up fuel and ignition corrections, idle speed management, and cooling fan activation control.

Built to OEM specifications and paired with a weatherproof Delphi connector, the HT-010302 is a clean, straightforward installation. The included Delphi plug and pins eliminate the need to source additional connectors, and the NTC thermistor output is natively calibrated in all Haltech ECU software. For cooling systems using a metric thread boss, see the HT-010300 (M12 x 1.5), and for smaller NPT applications, see the HT-010304 (1/8 NPT with Deutsch DTM-2 connector).