Engine Thermostat Guide & Diagnostic Information
The thermostat regulates coolant flow through the engine to maintain optimum operating temperatures.
Location on Vehicle
Inside a metal housing where the upper or lower radiator hose meets the engine block.
Typical Symptoms of Failure
- Engine slow to warm up
- Lukewarm heater output
- Low temperature gauge reading
Associated Diagnostic Trouble Codes
A malfunction in the Engine Thermostat can trigger the following OBD-II fault codes:
Estimated Replacement Cost
Typical cost to replace the Engine Thermostat: $150 - $400 (parts and labor).
Citations & Authority References
This technical part definition is cross-referenced with:
- EPA On-Board Diagnostics II Standard Specifications
- SAE J2012 Automotive Component Design Regulations