The ‘Dieselgate’ scandal is so big it doesn’t need an introduction, but how it works in practice still puzzles some people. The best way to see how the cheating software acts is to strap the diesel VW to a dyno and try to trick it into not knowing it was tested.
That’s what TFLCar did in the video posted below – they used a four-wheel drive dyno to fool the car into thinking it was on a normal road. They then switch it to just front wheel drive on the dyno and see what the discrepancies are, if any.
What is discovered is that the car, in this case a 2011 Jetta TDI, immediately detects it’s being tested, it flashes some lights on the dash, then apparently switches to another mode.
The torque and power curves it achieves are different to the run where all four wheels were being turned. The difference in maximum power is not as great as you would expect, but aside from the similar peaks, the rest of the curve does show a big difference in torque and power.