Is it possible to check the coolant temperature on a 2004 Chevy S-10 pickup while running?
Hook up a scanner (Live Data) and look at the ECT sensor temperature. That will take the dash gauge out of the equation.
The ECT sensor is a thermistor. A variable resistor whose resistance is affected by temperature.
The way they fail is usually an internal "open" or an internal "short" in the sensor.
If that happens the PCM will set an ECT sensor circuit voltage out of range (high or low) code.
It will be running and then the temperature starts to shoot up
shoot up to what?
I’m wondering if there is an easy way to check the actual coolant temperature and compare it to the gauge.
The only way to measure actual coolant temperature is to stick a thermometer in it.
You can use a diagnostic scan tool to read the coolant temperature in the computer.
If it shows something different , then the gauge is probably faulty.
If they agree, then the gauge works, but it doesn't eliminate the possibility that the temperature sensor is faulty, and both readings are wrong.
The only way to test if the sensor is working, is to pull it out and expose it to a known temperature. For example, by dunking it in boiling water, and then measuring the resistance ( should be around 177 ohms).
|
°C |
°F |
OHMS |
|---|---|---|
|
Temperature vs Resistance Values (Approximate) |
||
|
150 |
302 |
47 |
|
140 |
284 |
60 |
|
130 |
266 |
77 |
|
120 |
248 |
100 |
|
110 |
230 |
132 |
|
100 |
212 |
177 |
|
90 |
194 |
241 |
|
80 |
176 |
332 |
|
70 |
158 |
467 |
|
60 |
140 |
667 |
|
50 |
122 |
973 |
|
45 |
113 |
1188 |
|
40 |
104 |
1459 |
|
35 |
95 |
1802 |
|
30 |
86 |
2238 |
|
25 |
77 |
2796 |
|
20 |
68 |
3520 |
|
15 |
59 |
4450 |
|
10 |
50 |
5670 |
|
5 |
41 |
7280 |
|
0 |
32 |
9420 |
|
-5 |
23 |
12300 |
|
-10 |
14 |
16180 |
|
-15 |
5 |
21450 |
|
-20 |
-4 |
28680 |
|
-30 |
-22 |
52700 |
|
-40 |
-40 |
100700 |
but if the temperature doesn't shoot up with the engine off, but ignition on, then your gauge is probably indicating correctly, and you have a failed water pump or something. See Scotty's overheating videos.
Is it possible to check the coolant temperature
Yes. Why?
while running?
it's better if it is.
It will be running and then the temperature starts to shoot up. I’m wondering if there is an easy way to check the actual coolant temperature and compare it to the gauge.