Engine temp

[shospeed]

how do i know if the engine temp is accurate?

 

[SHOZ123]

You can back probe the temp connector with a voltmeter to see what the values are.

 

[shospeed]

Hmm... I see.
I will try that.
My sho seems to runa llitle hot every now & then.
Now I've changes both temp sensors,changed the thermostat, flushed the radiator and I burpt the radiator and the fan runs strong!!!
I honestly don't thing that the fan is coming on when its soposto.

Now I've put some after market gages on the dash so another consern is that the temp gage is not all that accurate sence I hade to remove the nittle to put the gages on.
Now it didn't run hot before that's why I don't think that's the issue but just putting it out there.

At this point anything will help.

 

[SHOZ123]

The fan turn on temperature is 216F.

 

[shospeed]

So how do I make sure it turns on at the right time?

And the back probe thing is in with sensor?

 

[SHOZ123]

The back probe is at the coolant gauge temperature sender.

Two ways to see what the temp is when the fan turns on. One is an IR temperature checker aimed at the t-stat. Not entirely accurate.

What I do is when flushing the radiator and it is full of straight water is to disconnect the upper hose, open the radiator cap and with a garden hose make sure it stays full. Then let the engine run checking the temp of the water coming out of the upper hose. This accurately test both the t-stat and the ECT assuming you have an accurate thermometer.

 

[1995SHO9]

X2 on what Shoz123 said.....

 

[shospeed]

The back probe is at the coolant gauge temperature sender.

Two ways to see what the temp is when the fan turns on. One is an IR temperature checker aimed at the t-stat. Not entirely accurate.

What I do is when flushing the radiator and it is full of straight water is to disconnect the upper hose, open the radiator cap and with a garden hose make sure it stays full. Then let the engine run checking the temp of the water coming out of the upper hose. This accurately test both the t-stat and the ECT assuming you have an accurate thermometer.

ok them sensor for the gage has only one wire and the one that goes to the computer has two cable running out.
my voltometer has a positive and the negative "2" wires.
so were do i connect what?

 

[Storm-Chaser]

To "verify" the accurracy of the temperature, whether it be that the sending unit is accurately sensing the temperature, the temperature gauge is accurately displaying it, or both, you have to have some other means to actually verify what the temperature actually is. This means either adding a second mechanical temperature gauge for direct comparison, or using an infrared temperature sensor.


If you read other pertinent threads, you should have come across several by Tom (Off Road SHO) where he talks about using an infrared thermometer. IR thermometers typically range from $60 to well in excess of $200 for something way beyond what's needed here.

AutoZone has started carrying an inexpensive infrared thermometer. Since they started carrying it, I have seen one displayed in every store I've checked. The IR thermometer costs $19.99 and is made in China. It has a temperature range of -31°F to +689°F . . . .

. . . . although I have no idea as to it's accuracy, as there is no information on the product packaging (ie. ±3° F or ±2-percent).

OEM Infrared Thermometer - $19.99

AutoZone part number - 25245

AutoZone SKU number - 951642

Warranty - 90 Days
​

how do i know if the engine temp is accurate?

 

[SHOZ123]

This appears to be hopeless.......

 

[shospeed]

This appears to be hopeless.......

I I'm really trying to solve this problem....

 

[SHOZ123]

To test the gauge temp sender in the car you need to pull the connector off a bit to get to the connector stem. Then put one lead of the voltmeter on the exposed stem and the other on the engine ground. Compare the voltage read out to the actual temperature.

If the engine ground is not good then the gauge may not read right so that is something to consider too. You should do an ohm check between the engine block and the negative battery terminal both when the car is off and running. Results should be less than .5 ohm.