Temperature sensor

[neal1980]

does anybody have the resistance values of the standard snb802 water temp sensor, i can not seem to find these anywhere. I know you can test it yourself with easy therm i think the programs called just trying to save a job...its friday i want a drink...

thanks

[K4TRV]

Is this the same item - extracted from a US Web page on Rover V8s.



Engine Coolant Temperature Sensor (aka: "thermistor" or "thermal resistor&quot

The Engine Coolant Temperature Sensor is threaded into a boss on the intake manifold. Note: this sensor contacts the coolant fluid, and thus its threads need to be sealed appropriately. When the engine is "cold", as determined by this sensor, the ECU richens the fuel mixture by lengthening the time injectors stay open. The ECU reduces the length of fuel pulses as the engine reaches normal operating temperature.

The Coolant Temperature Sensor should change resistance with heat, per the following specs.
10C (14°F) 9100-9300 Ohms
0C (32°F) 5700-5900 Ohms
20C (68°F) 2400-2600 Ohms
40C (104°F) 1100-1300 Ohms
60C (140°F) 500-700 Ohms
80C (176°F) 300-400 Ohms
100C (212°F) 150-200 Ohms


The Engine Coolant Temperature Sensor on our example system is marked "73355A", "Lucas", and "Made in UK". It has a 2-pin integral sealed connector. My local Auto Zone lists this sensor as part number SU5133 at $26.99, and they keep it in stock. Although I haven't been able to verify it, I've also been told this sensor is interchangeable with the sensor in a late 1980's VW Golf.

I'm told that these sensors are a relatively frequent cause of trouble on older Rover fuel injection systems. One installer told me he replaces the Engine Coolant Temperature Sensor whenever he does an engine swap.

[Cider Andy]

The values are in the 'bible' and pretty well match the ones above (except there's an error above: the '10°C' should read '-10°C').

[GreenV8S]

Easier to remember as 5kOhm at freezing, and halving per 20C rise.

[neal1980]

thanks for the replys, that should help me with the megasquirt set-up.

[Rum Runner]

Get the modwise kit off Dave , they come with a variable resistor ( adjustable so can set temp gauge )which fit directly on the existing wire but on the Land rover sender ( easy to get at ). Because the sender is in the coolant flow the reading is more accurate and the engine warms up a lot quicker than you think .
http://home.btconnect.com/djbeer/id24.html

Edited by Rum Runner on Friday 3rd August 19:13

[Chimjunkie]

Not convinced the Rover sensor has the same curve as the TVR sensor. Think it will only be accurate at the one point you calibrate it at!

[spend]

The same people who made your dials are the best place to get sensors from IMHO, my ETB replacements match their instruments quite accurately....

Dave

[Rum Runner]

Chimjunkie said:

Not convinced the Rover sensor has the same curve as the TVR sensor. Think it will only be accurate at the one point you calibrate it at!

Oh well seems to work well,the issue with the TVR sender is its on a long extension and not in the coolant flow, it also in winter months when there is good cold airflow it reads low and also takes a long time to warm up although the engine is hot quite quickly especially as all alloy and cocooned in a fibre glass body .
The engine takes ages to warm up according to the TVR sender.
On my second Chim and both been the same .

[David Beer]

I only suggest the "spare" sender for the temp guage readings, never investigated for the ECU. As for accuracy, the original was not in water so the "spare" could not be any worse, and so far as i have heard, never gone "tits up" as the TVR one will ! Dead thread from now on , i think.

[Rum Runner]

Sorry David thought we where talking about the temp sender for the gauge not the ECU ,must the the lack of sleep due to teething baby.