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92bird
01-29-2008, 05:11 PM
Does anyone know the resistance/voltage values for our factory ECT and IAT temp sensors?

I preferrable would like voltage to temperature comparison, but can also use kohms to temperature and do a conversion.

Thanks,

Jeramie

fturner
01-29-2008, 05:21 PM
Try this

http://www.fordfuelinjection.com/?p=29

You can look up the one for the ECT as well, but you'll find both sensors are actually the same.

92bird
01-29-2008, 05:24 PM
Thank you!! EXACTLY what I needed :)

Jeramie

Rpdboss
01-31-2008, 11:48 AM
I'm still trying to plan some stuff out in my mind about making varriable resistiors to alter the oxygen sensors readings to alter the A/F mixture to the desired one. going to need a three plate rheostat i believe to lean or richen the mixture. Then if that works then make one for the ACT and maybe later the MAF when I understand more about it and the stock limits of the stock equipment ones set by the computer. So there my idea is out there and anyone can run with it or help to contribute to it.:D

fturner
01-31-2008, 05:18 PM
I'm still trying to plan some stuff out in my mind about making varriable resistiors to alter the oxygen sensors readings to alter the A/F mixture to the desired one. going to need a three plate rheostat i believe to lean or richen the mixture. Then if that works then make one for the ACT and maybe later the MAF when I understand more about it and the stock limits of the stock equipment ones set by the computer. So there my idea is out there and anyone can run with it or help to contribute to it.:D

Interesting concept... but don't take this the wrong way, but you may need to rethink it a little bit with the O2's.

The car's computer puts the car into Open Loop state at about 85% VE Load (a stock SC has the ability to hit 130% load peak), or at WOT which ever event occurs first so to speak (more to it but thats the jist). The car ignores the O2 sensors in Open Loop so no matter how much you change the "voltage" of the sensor the computer ignores it anyway.

You will also have to consider that the narrowband sensors is very narrow. Essentually what you have a voltage change between almost 1 volt down to about 100mv's between an AFR of approximately 14.55 to 14.85. If you tweak the voltage to stay on the high side of voltage which is 1 volt you got a max of 14.55 or there abouts, and the computer will compensate that back to stoic which is 14.64.

What is happening when the car is in closed loop, is not a fixed AFR of 14.64, but a deliberate leaning and enriching of the AFR (done quite rapidly via adjusting the pulse width of the injectors) and based on the O2 sensor switching between lean and rich around stoic the average of those changes will produce an AFR 14.64. If your car tends to run rich, the computer will lean the mixture out till the O2 sensor switches, and these are called short term and long term fuel trims. Of course the computer does have limits on how far its allowed to "fix" this condition before a CEL occurs.

In order to do what your thinking, you'd need a wideband O2 sensor, and the computer in the car altered to handle it.... which I believe can be done ;).