Not usually but it will depend upon how you've got it wired. Mine kicks on with the ignition. Once on, it goes through the process of heating up the sensor prior to doing any actual reading. I supposed that if you had it wired to a constant hot and allowed it to warm up before cranking that it could but my question would be "why?".
Well heres the deal.....I cannot get my car to startup after changing putting on an 80mm pro-m and 42s. It just keeps turnin but wont go. a couple of times I got lucky and got it to idle (barely) by giving it wot but it never smoothed out. I am using a tweecer and have changed my maf curve, injector slopes to 42 and 50, my cranking pw vs time down to .6, and still it will not fire up. I am just not sure which way to go and how to tell if I am either flooding or starving the engine for fuel. any help would be great!!