Cold air at the same pressure in the same size container has more mass than hotter. More mass air means more power. This is why turbo cars have intercoolers. And its why they generally feel nore powerfull in cold weather.

If the ECUs temperature compensation equations are properly tuned, everything should run fine on cold days. Trouble is, it cant actually be tested or tuned unless you have those conditions available when tuning. But a good tuner should be able to approximate the settings so when the car does see a cold day, it still runs well and safe.

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Doing it for all the wagons out there