1994 Geo Tracker Base, 1.6 6, RWDFACTORY OEM SERVICE PROCEDURE

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 - °F (°C) Ohms
0 (-18) 14,650
19 (-7) 8100
39 (4) 4780
70 (21) 2350
100 (38) 1250
160 (71) 400
210 (99) 190
EGR TEMPERATURE SENSOR RESISTANCE

Temperature - °F (°C) Ohms
68 (20) 214,000-313,800
104 (40) 90,900-125,700
140 (60) 42,100-55,500
176 (80) 21,100-26,500
212 (100) 11,200-13,600
INTAKE AIR TEMPERATURE (IAT) SENSOR RESISTANCE

Temperature - °F (°C) Ohms
0 (-18) 14,800
19 (-7) 8250
39 (4) 5200
70 (21) 2500
100 (38) 1300
160 (71) 450
210 (99) 200

Manifold Absolute Pressure (MAP) Sensor 

For information on MAP sensor, see ENGINE SENSORS & SWITCHES in I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.

OXYGEN SENSOR HEATER RESISTANCE

Application Ohms
MFI (Calif. & New York) (1) 11.7-14.3
TBI (Federal) (2) 3.0-5.5
(1) With temperature of 68°F (20°C).
(2) With temperature of 73°F (23°C).
THROTTLE POSITION (TP) SENSOR RESISTANCE

Application Ohms
TBI - Federal
Between Terminals 2 & 4 3500-6500
Between Terminals 3 & 4 (1) 0-500
Between Terminals 3 & 4 (4) Infinity
Between Terminals 4 & 5 (2) 300-2000
Between Terminals 4 & 5 (3) 2000-6500
MFI - Calif. & New York
Between Terminals 1 & 3 3500-6500
Between Terminals 1 & 2 (5) 0-500
Between Terminals 1 & 2 (6) Infinity
Between Terminals 1 & 4 (2) 300-2000
Between Terminals 1 & 4 (3) 2000-6500
(1) With .012" (.30 mm) feeler gauge installed between throttle stop screw and lever.
(2) Throttle valve at idle position.
(3) Throttle valve at fully open position.
(4) With .022" (.56 mm) feeler gauge installed between throttle stop screw and lever.
(5) With .020" (.50 mm) feeler gauge installed between throttle stop screw and lever.
(6) With .031" (.80 mm) feeler gauge installed between throttle stop screw and lever.

Vehicle Speed Sensor 

For information on vehicle speed sensor, see ENGINE SENSORS & SWITCHES in I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.

Fig 1: Identifying TP Sensor Terminals
G94C44166Courtesy of GENERAL MOTORS CORP.
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