Does anyone know where I can get a replacement coolant Temperature Sensor or what it really is, is a "thermistor". I want one that would have a different temperature curve so that when the motor is at 200 degrees F it would make the computer think it was at 230 degrees F thus the ending result would be that the fan would come on at 200 and turn off at 190. I'm putting this in a 1992 Chevy Camaro 3.1L V6 and the Hypertech Fan Switch won't work, which I had to find out the hard way.
thanks

 

Why not a simple manual override to start fan?

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Chat Soon,
KED85
Karl
1985 Firebird 2.8 to 3.4 swap project for Smog Happy LA, CA

 

You would probably have to reprogram your chip to do that. Or you may be able to figure out the voltage that corresponds to the temperatures that you want, and put a resistor in there to slightly lower/raise the reading. Either way it's going to be complicated.

Oh, don't forget to put a lower temperature thermostat in, since there's no sense in having the fan going if the t-stat is closed at 195.

Alex

 

The Resistance idea is a good idea but it works the oppisite way, I need less resistance to equal a higher temp. to the computer, thats just how it works, HOW much do those reprogramed chips cost and can a person just get one programed to stock spec and can a person get any better MPG with a new chip.

To the person who wrote about just putting in a switch, NO THANKS, the idea is to have it automatic so if you sitting there in traffic fighting stupid people, that I won't forget to have the fan come on, and it would just be a pain, oh I got to turn it on again.

 

Yeah, I was thinking that's what would happen. You could put a resistor in parallel (Ohm's Law) with the sensor to lower it though. I'm an electrical engineering student, so if you get me the exact numbers I can work it out for you

If you go to the DIY PROM board on this site and read the PROM burning FAQ at the top of the page, you will see some example prices. Doing it just to reprogram your fan turn on times would be a waste of money in my opinion, but you would probably be able to get some extra horsepower and milage out of the car.

I'm thinking of getting a programmer for my 6 so I can fool around with it, I can let you know how it turns out.

 

Why wouldn't the Hypertech fan switch work? Was it a different size thread? If so, did you look for a brass adapter? I had to use one to adapt my aftermarket mechanical "v8 water temp gauge" to my 2.8.


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-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards
---Think your car could be pic of the week? Visit http://www.f-body.net for details!

 

Hey, I just saw this on the General board:

Temperature (F) CTS Resistance (ohms)
210 -----------------------------185
160 ----------------------------450
100 -----------------------------1800
70 ----------------------------3400
40 --------------------------7500
20 -------------------------13,500
0 -------------------------25,000

Too bad it doesn't have all the data points that you need.

 

a fan switch by Hyper tech won't work because it's a FAN SWITCH not a thermistor, the 3.1L uses a thermistor that tells the computer what the temp of the motor is and the computer turns on the ONE FAN.

AlexJH
see if I add another resistor in line with the thermistor it will hurt me more, see remember this is a thermistor, I need less resistance at the higher temp. , I have the factory 1992 Camaro manual, I figure I need 100 ohms of resistance at 212 degrees F to fake the computer into thinking that the motor is 230 degrees F. Thanks guys

 

So I've been asking around for this:
Any ideas for suppliers let me know
Do you all know of a place where I can get a thermistor that would have a different or custom Temperature vs. Resistance curves or have one made to do the same thing??? I need it to be like a GM thermistor where you can screw it into a block or head. And it would need to be 9500 ohms of resistance at 32 degrees F and about 100 ohms at 212 degrees F. Cost is no problem and if I have to buy more then one to have it custom made, no problem. Thanks I really need something like this.