Purpose of the Sensors
To provide a voltage value to the Engine Control Computer which varies
according to the amount of resistance through the sensor leads which is
determined by a variable thermistor/resistor based on the temperature
around the pickup/probe end of the sensor.
Symptoms
- Hard starting hot or cold
- Sudden poor fuel mileage
- Excessive fuel smell when idling
- Stalling on cold start up
- Flooded no start condition after short trips (hot soak similar to
vapor lock)
Testing
NOTE: Testing the ECT sensor REQUIRES the coolant level to be FULL
and at the proper dilution for an accurate reading!
- Remove connector from sensor (varying
locations)
- Test for resistance across the two
contacts on the sensor
- Values should be as noted below
ECT/IAT Sensor Resistance Specifications
Temperature……
Engine Coolant/Intake Air Temperature Sensor Values
Degrees F |
Resistance in Ohms |
| |
|
248 |
1,180 |
230 |
1,550 |
212 |
2,070 |
194 |
2,800 |
176 |
3,840 |
158 |
5,370 |
140 |
7,700 |
122 |
10,970 |
104 |
16,150 |
86 |
24,270 |
68 |
37,300 |
50 |
58,750 |
| |
|
|
