Question 1

What does P0116 mean?

Accepted Answer

P0116 - ECT Circuit Range/Performance. The ECT sensor doesn't match expected warm-up patterns.

Question 2

What are the symptoms of P0116?

Accepted Answer

Check engine light, Slow warm-up, Heater blows lukewarm, Poor fuel economy

Question 3

What causes P0116?

Accepted Answer

Stuck-open thermostat (most common), Failed ECT sensor, Cooling system issue, Low coolant level

Question 4

How much does it cost to fix P0116?

Accepted Answer

Typical repair cost: $20-$300. If heater is also lukewarm, thermostat is stuck open. A new thermostat is $15-50.

P0116 — ECT Circuit Range/Performance

Don't guess — diagnose P0116 the right way