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Engine Controls - Sensor Operating Range Charts: Introduction

Sensor operating range information can help determine if a sensor is out of calibration. An out-of-calibration sensor may not set a trouble code, but it may cause driveability problems.

NOTE: Unless stated otherwise in test procedure, perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance.
ENGINE COOLANT TEMPERATURE (ECT) SENSOR RESISTANCE

Temperature Ohms
86°F (30°C) 1500-2000
176°F (80°C) 275-375
HEATED OXYGEN SENSOR (HO2S) RESISTANCE

Terminals No. Ohms
1 & 2 0.0-19.9
HEATED OXYGEN SENSOR (HO2S) VOLTAGE

Condition Volts
Lean Approx. 0.2
Rich Approx. 0.7
INTAKE AIR TEMPERATURE (IAT) SENSOR RESISTANCE

Terminals Ohms
Measure Between Sensor Terminals
1.8L Turbo Approx. 1600-2800
2.8L Approx. 1500-3500
KNOCK SENSOR RESISTANCE (1.8L TURBO)

Terminal No. Ohms
1 & 2 Infinity
1 & 3 Infinity
2 & 3 Infinity