Those hot-wire MAF sensors (like the one in my car) are based on equilibrium, not air temperature. The equilibrium airflow is going to be the same regardless of how hot or cold it is outside.
Supposedly, the sensor will compensate for temperature changes, but in my own experience that isn’t even close to being the case. Sometimes in the winter you also can hit higher maf frequencies that weren’t dialed in during the summer months, causing problems as well.
A hot-wire maf will compensate, though only to a certain degree. My car isn’t that sensitive but maybe others are.
your semi right chris , if we were talkin about a older car it could get hairy between w/s tunes . newer cars are way smarter and can compensate for weather ,fuel , and so on as long as its tuned right
Anyone that (properly) tunes a vehicle will interpolate between known points and extrapolate beyond. GM happens to use MAF and MAP sensors on vehicles to obtain actual values. VE tables are primarily used for backup in the event of MAF failure, but in some instances the inputs of both are used. Above a set engine speed the MAF takes over fully in most vehicles. MAF tables are calibrated from the factory, but generally are set to err on the side of caution. VE tables even more-so.
IAT sensors are used to calculate air density, so temperature shouldn’t have much of an affect if ANY if the sensor is in good working order. I certainly wouldn’t go saying that a summer tune = winter destruction…
Again, like I said on the last page, it’s obviously dependent on platform. With MY car and my own personal EXPERIENCE over the last 3 years of owning it and tuning it, I’ve found out that the factory MAF/ecu is not sensitive enough to pick up on changes in air density. SO, in the WINTER, when it’s COLDER, it needs to be re-calibrated. Also, the LSJ motor has a non-return style fuel system, so the #4 cylinder bank (furthest away on the rail) runs especially lean when the temperature changes and melts pistons and other fun things of that nature.
I would love to see data that supports this. Most GM VCM’s are extremely open. I don’t know of a single feature that it doesn’t have that I would desire (especially when you consider a custom OS).
I will admit that my tuning has been limited to eManage, crome, crome pro, hondata, HP tuners and flashpro, but out of any of them HP tuners is by far the most in depth. Most of others have such horribly generic tables and options that I feel like I’m playing with a Fisher-Price product.