Calorstat TH6989.88J Engine Coolant Thermostat

Engine Coolant Thermostat Housing Overview

Calorstat TH6989.88J is an engine coolant thermostat with a plastic housing, built for precise coolant flow control in select Audi applications. It uses a black plastic housing with a rubber gasket seal to support a secure, leak-resistant installation.

Compatible with 2005-2009 Audi A4 Quattro, 2006-2009 Audi A6, 2006-2008 Audi A4, and 2005-2008 Audi A6 Quattro, this thermostat housing is a direct-fit cooling system service part for OE-style replacement needs. The TH6989.88J part number is also referenced in cross applications for the same vehicle coverage.

Key Features

• Engine coolant thermostat with integrated plastic housing
• Black plastic construction for OE-style cooling system service
• Starts to open at 190.0 degrees for temperature regulation
• Gasket and rubber seal included for housing sealing
• Seven bolt holes for mounting
• Calorstat TH6989.88J replacement thermostat housing

Detailed Product Description

Calorstat TH6989.88J is a plastic housing thermostat assembly used to regulate coolant temperature in the engine cooling system. The thermostat begins to open at 190.0 degrees, helping maintain proper operating temperature by controlling coolant flow through the system. Its plastic housing design, gasket seal, and rubber sealing material support a clean service replacement on covered Audi models. Vernet is an OE supplier to Audi, and this part number is listed for Audi A4 Quattro, Audi A6, Audi A4, and Audi A6 Quattro applications. This part cross-references Gates 34721 for the same application.

Common Cooling System Issues It Can Address

• Engine running too cool or taking too long to reach operating temperature
• Temperature fluctuations caused by a worn thermostat
• Coolant seepage at the thermostat housing seal surface
• Check engine light concerns related to coolant temperature regulation
• Cooling system service needs on Audi A4 and A6 platform vehicles

Installation Notes and Tips

Verify the housing style, bolt-hole count, and temperature rating before installation. Inspect the mating surface, replace damaged coolant hoses or clamps as needed, and clean the sealing area thoroughly so the gasket can seat correctly. After installation, refill and bleed the cooling system according to the vehicle service procedure to remove trapped air.

Quality Assurance

Calorstat TH6989.88J is built with a plastic housing, gasket seal, and rubber seal material to match the listed application requirements. Vernet’s OE supplier relationship with Audi supports confidence in the application coverage for these Audi A4 and A6 platform vehicles.