Parts for your 2016 Subaru Xv-Thermostat

2016 Subaru XV Thermostat: What it Does and When to Replace It

A thermostat is absolutely fitted to the 2016 Subaru XV with the FB20 2.0‑litre boxer engine. This is confirmed by Subaru’s factory service manual for the 2016 XV (Cooling System section) and the Subaru Genuine Parts catalogue, which both list a wax‑pellet thermostat in the coolant outlet housing.

On this XV, the thermostat’s job is simple but critical: it helps the engine warm up quickly and then keeps it sitting in the sweet spot for temperature under all sorts of driving. By staying shut when the engine’s cold, it speeds up warm‑up for better fuel economy, smoother running and lower emissions. Once the coolant reaches operating temperature, the thermostat opens and meters flow to the radiator so the XV doesn’t overheat on a hot day up the Kaimais or overcool on a chilly Canterbury morning. Typical opening temperature is around the low‑90s °C, and the engine computer keeps an eye on it, if it’s running too cool for too long, it can even log a P0128 code.

Owners thinking about servicing their 2016 Subaru XV thermostat should treat it as a “replace when needed” item rather than on a strict schedule. It’s worth replacing whenever the cooling system is already apart (for example, water pump or hose work), after any significant overheating, or if any of the classic symptoms show up.

• Slow warm‑up, lukewarm heater, or poor fuel economy (often stuck open)
• Temperature spikes or quick overheating after start‑up (often stuck closed)
• Temp gauge that hunts around, or a P0128 fault stored

The thermostat on the FB20 sits in the lower radiator hose housing near the water pump. Always fit a new Subaru‑spec thermostat and seal/O‑ring, and orient it exactly as per the service manual (pay attention to any alignment mark or jiggle pin position). Refill with the correct Subaru long‑life blue coolant and bleed the system properly using a spill‑free funnel, heater on full hot, and gentle hose burping to clear air. Don’t overtighten the housing bolts—use the factory torque spec. After the job, they should check for leaks, confirm the radiator fans cycle normally, and make sure cabin heat is strong once warm.

Sticking with genuine‑quality parts, fresh coolant at the logbook interval, and good bleeding technique will keep the XV’s temperature rock‑steady and the engine happy for the long haul.

FAQs

What temperature does the 2016 Subaru XV thermostat open?
Most FB20 thermostats begin opening in the low‑90s °C range and are fully open a few degrees higher. That lets the engine reach operating temp quickly, then hold it steady in traffic or on the open road. Exact specs depend on the part fitted, so they should check the service data on the thermostat box or the Subaru manual.

Where is the thermostat on a 2016 Subaru XV?
It’s housed in the lower radiator hose outlet near the water pump on the front of the engine. Access typically involves draining some coolant, removing the lower hose and the outlet housing, then swapping the thermostat and seal before refilling and bleeding.

What are the signs the thermostat needs replacing?
Slow warm‑up, poor heater performance, a temp gauge that wanders, sudden overheating, or a P0128 code are common flags. After any overheat event, it’s smart to replace the thermostat as cheap insurance, along with inspecting the cap, hoses and coolant condition.