@BarryHunt008 Have you tried measuring it without you in the car?
My guess would be low initial air flow. But if it still spikes without the human source, it's coming from somewhere else.
@BarryHunt008 你试过在没有你在车里的情况下测量它吗？
我的猜测是初始气流较低。但如果它在没有人为来源的情况下仍然飙升，那么它来自其他地方。