Generating the brake spark can be as simple and inexpensive as a flickering LED... for example from an LED candle you get at DollarTree for, uhh, $1. Or there are many pre-built flickering/random blinking circuits used in modeling to simulate campfires, welding, etc.
More interesting is knowing WHEN to trigger or turn on the sparking. In the example you give, the engine's electronics KNOWS WHEN it is slowing down and hence KNOWS WHEN to turn on the lighting effect. If attempting to add this effect after-the-fact, I'd be surprised to find any engine electronics that has an output or trigger signal indicating when the engine is braking or rapidly decelerating. For example, I know that in MTH PS2/3 you can get a brake squeal sound when rapidly decelerating....but I'm fairly certain this event is not available as an electrical trigger signal that can turn on a flickering/sparking LED circuit.
In which case I'd think you need to concoct a method to detect rapid deceleration by somehow monitoring the speed of the engine. There are many ways to detect deceleration which can be elaborated upon if there's interest.
