Investigators will look at the trains' braking performances, wheel and track conditions, and speed and other information from data recorders, Weener said.

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Investigators will look at a number of things, including the trains' braking performance, wheel and track conditions, and speed and other information from data recorders, Weener said Saturday.

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The parts included "brakes, brake pads, brake shoes, ignition coils, water pumps, window regulators, suspension sway bar links, wheel hubs, anti-lock braking sensors, control arm bushings, transmission filters, pitman arms, tie rod ends, and suspension air springs, " the papers add.

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The A3 also boasts two paddles behind the steering wheel that let drives control the level of regenerative braking that adds charge to the battery.

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