P0116 on Chevrolet
Engine Coolant Temperature Sensor 1 Circuit Range/Performance
P0116 on Chevrolet vehicles indicates engine coolant temperature sensor 1 circuit range/performance. Au7o has documented this code across 1 Chevrolet model — most commonly on Cobalt. P0116 means the engine control module detected an engine coolant temperature (ECT) sensor reading that is within wiring limits but doesn't make sense — for example, it doesn't rise as the engine warms up, or it disagrees with other temperature data. The ECT sensor reports coolant temperature, which the computer uses for fuel mixture, ignition timing, cooling-fan control, and emissions monitors. An implausible reading can cause poor fuel economy, hard cold starts, or failed emissions readiness. It is generally drivable but should be fixed for proper engine management. Typical repair costs on Chevrolet range from $150 to $600, depending on the specific model and root cause.
Common Causes of P0116
- •Faulty or drifting engine coolant temperature sensor
- •Stuck-open thermostat (engine never reaches normal temp)
- •Low coolant level or air in the cooling system
- •Wiring or connector resistance affecting the signal
- •Sensor reading inconsistent with intake-air temperature at cold start
- •Corroded sensor connector
- •PCM fault (less common)
P0116 on Chevrolet by Model
Chevrolet Cobalt(1 issue)
- Ecotec Thermostat Housing and Water Pump Coolant Leak — Slow Loss with No Visible Puddle2005-2010
On the 2.2L/2.4L Ecotec the thermostat is integrated into a plastic housing on the back side of the engine facing the firewall, and the water pump sits behind the timing cover on the passenger side. Both are recurring leak points. The rear thermostat housing seal hardens and the housing itself corrodes and seeps, and because the leak is tucked against the firewall the coolant evaporates on the hot block instead of dripping — so owners chase a steadily dropping reservoir with no puddle in the driveway, a complaint that appears over and over on the Cobalt forums. The water pump leaks at its gasket toward the passenger side, and because it is timing-chain driven, a leaking pump can wash the front of the engine and contaminate the chain area. A slow leak that runs the car low leads to overheating and, on the Ecotec, a warped or cracked head.
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View P0116 across all makes →Frequently Asked Questions
What does P0116 mean on Chevrolet?▼
P0116 stands for "Engine Coolant Temperature Sensor 1 Circuit Range/Performance." P0116 means the engine control module detected an engine coolant temperature (ECT) sensor reading that is within wiring limits but doesn't make sense — for example, it doesn't rise as the engine warms up, or it disagrees with other temperature data. The ECT sensor reports coolant temperature, which the computer uses for fuel mixture, ignition timing, cooling-fan control, and emissions monitors. An implausible reading can cause poor fuel economy, hard cold starts, or failed emissions readiness. It is generally drivable but should be fixed for proper engine management. On Chevrolet specifically, this code is documented across 1 model.
What causes P0116 on Chevrolet vehicles?▼
Common causes on Chevrolet: Faulty or drifting engine coolant temperature sensor, Stuck-open thermostat (engine never reaches normal temp), Low coolant level or air in the cooling system, Wiring or connector resistance affecting the signal, Sensor reading inconsistent with intake-air temperature at cold start. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0116 on a Chevrolet?▼
Repair costs on Chevrolet range from $150 to $600, depending on the specific model and root cause.
Which Chevrolet models have P0116 documented?▼
Au7o has documented P0116 on 1 Chevrolet model: Cobalt.