i need to datalog an extra IAT and an extra MAP sensor.....
i can artificially create my own 5v source but i figured this would just be easier
the reason why i need a 5v source for the IAT sensor is that my datalogger doesn't datalog thermistors. So, i know, you are asking yourself if it can't datalog thermistors why are you bothering using an IAT and messing with the 5v source?
well, thanks to my friends on the DIY_EFI email list they explained to me that i can install a bias resistor inline with the signal wire to the IAT. Then supply a 5v source to the sensor and then DATALOG that 5v source as it changes with the resistor
Then all i have to do is do a couple tests with a IAT sensor, thermometer, and some hot water.
Lastly, configure the software (Xv = X*) and then wala, i can datalog my IAT readings
I was also told that the IAT sensor's thermistor isn't a linear curve but linear at first and then curves at the end. I am not worried about this, it will be close enough for my purpose
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Craig, since only the TPS and the MAP receive the 5v source...you think it would be ok to tap into that 5v supply for 2 more sensors? I mean i dont think the load could be that great
thanks for your help
edit: As you already know, The IAT has its own signal coming from the ECM. I just looked at my modified pin_out list (i installed a single 48pin bulkhead connector to clean up wiring and had to make one) and looked and confirmed what you told me.
here is a nice link to the specs on the GM IAT sensor:
http://forum.aempower.com/bbs/download.php?id=312