1990 Chevrolet Caprice Base, 4.3 Z, 4L60/MD8FACTORY OEM SERVICE PROCEDURE

Sensor Operating Range Charts

COOLANT TEMPERATURE RESISTANCE VALUES (1)

Temperature - °F (°C) Ohms
210 (100) 185
160 (70) 450
100 (38) 1800
70 (20) 3400
20 (-7) 13,500
0 (-18) 25,000
-40 (-40) 100,700
(1) Measure resistance across sensor terminals.
MAP SENSOR VOLTAGE RANGE (1)

Altitude - Feet Volts
Below 1000 3.8-5.5
1000-2000 3.6-5.3
2000-3000 3.5-5.1
3000-4000 3.3-5.0
4000-5000 3.2-4.8
5000-6000 3.0-4.6
6000-7000 2.9-4.5
7000-8000 2.8-4.3
8000-9000 2.6-4.2
9000-10,000 2.5-4.0
(1) Measured at sensor, or as seen on Scan tester.
MANIFOLD AIR TEMPERATURE SENSOR RESISTANCE VALUES (1)

Temperature - °F (°C) Ohms
210 (100) 185
160 (70) 450
100 (38) 1800
70 (20) 3400
40 (4) 7500
20 (-7) 13,500
0 (-18) 25,000
-40 (-40) 100,700
(1) Measure resistance across sensor terminals.
OIL TEMPERATURE SENSOR RESISTANCE TEST (CORVETTE) (1)

Temperature - °F (°C) Ohms
210 (100) 185
160 (70) 450
100 (38) 1800
70 (20) 3400
40 (4) 7500
20 (-7) 13,500
0 (-18) 25,000
-40 (-40) 100,700
(1) Measure resistance across sensor terminals.
OXYGEN SENSOR VOLTAGE TEST (1)

Condition Volts
Lean .1
Rich .9
(1) Measure voltage between O2 sensor ground and signal terminals at ECM.
PRESSURE SENSOR VOLTAGE RANGE (1)

Altitude - Feet Volts
Below 1000 3.8-5.5
1000-2000 3.6-5.3
2000-3000 3.5-5.1
3000-4000 3.3-5.0
4000-5000 3.2-4.8
5000-6000 3.0-4.6
6000-7000 2.9-4.5
7000-8000 2.8-4.3
8000-9000 2.6-4.2
9000-10,000 2.5-4.0
(1) Measured at sensor.
Factory Service Tools

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