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timreid 04-21-2003 09:40 PM

How to Check Engine Temperature
How do or can I check the operating temperature of my engine by using an external temperature gauge? I was thinking about using a digital thermometer, but I'm not sure were to place the metal temperature sensor on the engine. One spot I was considering is the thermostat housing next to were the small L shape coolant hose is connected, would this spot provide a good temperature reading?
Thanks,enjoy your drive, timreid

timreid 04-21-2003 11:14 PM

Sorry, Yes I'm referring to the coolant temperature tkamiya. When you requested the check, where you comparing the readings to your temperature gauge, what were your readings? I want to compare the external readings to my dash temp gauge, also note at what temperature the aux fans turn on and off. timreid, enjoy your drive

h_shek 04-21-2003 11:57 PM


you properly know this but just my 2 cents...

there are 2 sensors on the thermostat housing. Since they are independent I just check the readings on both and if they are the same than I believe both sensor is working properly.

one sensor reports the temp to your odo..

the other sensor send readings to your A/C system which you can read the temp in diagnostic mode.

I think considering they are independent, comparing the 2 readings very much gave me confidence that my sensors are in good conditions. Unless these sensors have a history of failing at the same rate and at the same time. Highly unlikely I would guess.

aux fan?? I think they come on at 100 degree and off at 95 degree without modification. They also come on at XX bars when the A/C is on.

Arthur Dalton 04-22-2003 12:44 AM

Gauge temp sensor is single wire at thermo housing..
Resistance sustitution [ RS close tol -1% ] will verify gauge calibration..
With ohm meter , one can also verify sensor accuracy after gauge test..

60C-110 ohm
80C -67
100C - 38

This sensor has different values than ECT sensor that feeds ECU for mixture/idle mappings...

timreid 04-22-2003 04:28 PM

Arthur, I was searching across the site for such info for my 400E, and I came across you sharing your knowledge several times, again thanks. Electrical has always been a challenging one for me, but tomorrow I will dust off my ohm meter and see what I come up with.
enjoy your drive, timreid

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