What makes a piston go on a Hyundai Elantra 2013 with only 96 000 km on it?

Yes it does. A fuel injector is a device that atomizes and then delivers the fuel into the cylinder just before the piston squeezes the fuel and air mixture and the spark from the spark plug fires. Ergo your 2000 Hyundai Elantra being a 4 cylinder vehicle, has 4 fuel injectors.

You're describing a powertrain problem. If you're a 2nd owner & this vehicle has less than 60,000 miles (96,000 km), it's still under warranty. If you are the original owner and the vehicle has less than 100,000 miles (160,000 km), it's still under warranty.

3000 miles (or 5000 KM) or 3 months, whichever comes first.

60,000 miles is the typical recommended interval for timing belt replacement. The belt can become worn and skip a tooth or even break. In that event, the pistons can collide with the valves and cause a considerable (and expensive) amount of damage. Changing the timing belt at recommended intervals is good insurance to protect against valvetrain and piston damage due to belt failure.

you must squeeze the calipar PISTON back i use a G clamp to compress them!

Hmmm.... rear strut bushings.

The timing belt is normally replaced at 100,000 km (approx. 60,000 mi), but must be checked for wear and tear starting 75,000 km(approx. 45,000 mi) along with a major tune-up.

The switch near the shifter is the ECT (transmission control) which selects NORMal driving mode, and PoWeR mode. It is the battle between economy (NORM) and driving performance (PWR). As tested, the PWR mode delays your A/T upshift to a higher RPM. This utilizes your engine's higher revs, but really cuts into fuel economy.

Hope this helps.

Could be that plug wire, pull that plug wire and see if there is a spark while cranking the engine( you will need an asisstant). 2nd thing, could be a fowled or bad fuel injector.

if you haven't already try a tune up, and also have the (maf) mass air flow sensor checked.