Do I need to leave my Accessport plugged in all the time?

No. This is one of the most common misunderstandings about how the Accessport works, and the answer is genuinely reassuring. When you flash a map, the Accessport writes it into the car's ECU. The tune then lives in the car. Unplug the device, put it in a drawer, and the car keeps running that map indefinitely. The Accessport is a tool for changing and monitoring what is in the ECU, not a box the engine depends on to run. So the only reasons to leave it connected are the ones you actively want: watching live gauges such as boost, intake air temperature or knock monitors while you drive, or recording a datalog for your tuner. Both are legitimate, and plenty of owners keep it mounted for exactly that. But it is a choice, not a requirement. There are good reasons not to leave it plugged in permanently. It is an obvious, valuable and easily grabbed item sitting on your dash or windscreen, and a visible sign the car is modified - both of which matter for parking in public. A cable running across the interior is also one more thing to catch on things and one more connector to wear out. One genuinely important thing to understand instead: the Accessport marries to a single vehicle. When you flash a car, the device locks to that VIN and cannot be used on another car until you uninstall it, which returns the ECU to the stock map and releases the device. This matters in two situations. First, before selling the car, uninstall the Accessport if you intend to keep the device. If you sell the car still flashed and the device married to it, you have effectively sold your Accessport too. Second, before dealer service or any warranty work, return the car to stock. This is straightforward - it is a normal function on the device - and it is far better done in your driveway than discovered by a technician reading the ECU. Keep in mind that returning to stock removes the map but does not erase the ECU's record that reflashes occurred, so this is damage limitation rather than invisibility. A practical note if you do mount it: pick a position that does not obstruct your view and does not put the cable across the steering wheel or gear lever. There are dedicated mounts for the VB including vent docks and gauge pod adapters, which are tidier and safer than the suction mount most people start with.