What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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Sir_Hiro

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Thanks! Very nice idea with the separate fuel tank with the filling point next to the regular gas cap!

We hit -31 Fahrenheit yesterday morning so long story short I didn't even bother to try and start the car (or go outside for that matter). Today is better at -11F but still, cold starts are a bit iffy this time of the year.
I think the coldest where I live in MI this year has hit -10 and the ole TDI didnt start lol.
 

lowh07

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Grille finished up. Really prefer the quality, depth, and design of the OEM. The bumper cover shipped so hopefully I’ll have the front end back together by this weekend
IMG_0514.jpeg
 

Charlie207

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Last winter I had to start my Yukon when it was parked outside overnight and it was -17*.
It started but ran a little weird for about 10 minutes.

I get some weird idle-characteristics sometimes when it's cold: Let off the gas, and the rpms will stay revving, then drop. Or, spin the tires on ice and zip around in circles, but come to a quick stop, and the engine dies. It's annoying, but I assume it's an artifact of my swapped engine & hardware mods, plus the email tune that can never be perfect without the tuner sitting in the passenger seat reading/writing the live-data.
 

Grady_Wilson

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I get some weird idle-characteristics sometimes when it's cold: Let off the gas, and the rpms will stay revving, then drop. Or, spin the tires on ice and zip around in circles, but come to a quick stop, and the engine dies. It's annoying, but I assume it's an artifact of my swapped engine & hardware mods, plus the email tune that can never be perfect without the tuner sitting in the passenger seat reading/writing the live-data.
Yeah, mine runs a little rough, doesn't seem real smooth until the entire engine has gotten a little bit of heat into it.
After that, it does seem to be slightly down on power but it has never died off throttle.
 

Charlie207

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Air that cold has pretty much zero moisture in it.
Moisture helps cars to gain power because of how it affects combustion.
That's why people uses to install water injection systems to run higher timing advance settings.
I'm not sure that's really what's happening, or you may only be aware of a sliver of the larger picture.

Water injection is to fight pre-detonation, yes. But... not to offset atmospheric conditions such as humidity... you can also use menthol or washer fluid or apple juice if you feel like it; you're just cooling down the cylinder temps to prevent pre-detonation. The difference between a cold damp day and a cold dry day aren't much with regards to an engine noticing it. It's all about air density.

Colder air, regardless of water composition, will be denser vs. hotter temp. air. The denser air (especially with a turbo) provides a more efficient burn, allowing for more fuel (and/or boosted air) and power.

I can tell you right now that I've never heard of anyone complaining about dry vs. humid air in the winter with regards to power gains.
 

Dirty looks

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The heater installation is pretty neat, but the 3rd battery on a hinged mount is brilliant!
Thanks.. unfortunately I had to raise the battery even higher when I installed the new front bumper. The front skid plate wouldn't clear. I now have to remove the electric fan shroud and pull the battery out the top to change it out. The battery couldn't make the ark down anymore.
 

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Doubeleive

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I get some weird idle-characteristics sometimes when it's cold: Let off the gas, and the rpms will stay revving, then drop. Or, spin the tires on ice and zip around in circles, but come to a quick stop, and the engine dies. It's annoying, but I assume it's an artifact of my swapped engine & hardware mods, plus the email tune that can never be perfect without the tuner sitting in the passenger seat reading/writing the live-data.
I would use a scanner or if you have autocal or other usb dongle & download EFI live (it's free) on a laptop or windows tablet and do a cold start drive record
then look at all the data points and see what's up.
I guess the tech2 can do a drive record also but I have never tried it.
 

Charlie207

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I would use a scanner or if you have autocal or other usb dongle & download EFI live (it's free) on a laptop or windows tablet and do a cold start drive record
then look at all the data points and see what's up.
I guess the tech2 can do a drive record also but I have never tried it.
I have the AutoCAL V3, and was wondering if I could see the live data, or a log. I haven't really played around with the logs to see if I could load them and observe. Or, is the BlackBear stuff locked down for viewing?
 

Doubeleive

Wes
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I have the AutoCAL V3, and was wondering if I could see the live data, or a log. I haven't really played around with the logs to see if I could load them and observe. Or, is the BlackBear stuff locked down for viewing?
I don't know about the actual tune but efi live will do live data, a drive record or playback your submitted drive logs
 

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