P0118

Engine Coolant Temperature Sensor 1 Circuit High

Severity: Medium Fuel & Air Metering Generic OBD-II Code Est. Repair: $60 - $180

Schedule diagnosis soon. Continued driving may worsen the issue.

What Does P0118 Mean?

ECT circuit voltage high (interpreted as extremely cold). Engine may stay in open-loop longer.

Common Symptoms

CEL
Gauge may read cold
Poor MPG
Hard start when warm

Possible Causes

Failed ECT
Open wiring
Poor connector
Low coolant

How to Fix P0118 – Repair Guide

Check coolant
Test sensor resistance
Inspect wiring
Replace ECT
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Disclaimer: Information is for educational reference only and does not replace professional diagnosis. Actual causes and costs vary by vehicle make, model, year and condition. Always verify with a qualified technician.