The only way to "check" a piston would be to remove it and visually inspect for damage and wear.
HOWEVER
You can run a compression test and get a good idea whether the piston is functioning somewhat correctly.
Yes. If the timing is off, the pistons will damage the valves
Yes it will.
autozone will do it for you for free.
you need access to an OBDII scan tool in order to reset the check engine light on any vehicle 1996 or newer. autozone or advanced auto usually provide this service for free
The engine is an interference engine, if the timing belt breaks or slips it will cause damage to the valves and possibly the pistons.
common problem with 1998 mystique check engine light on
Engine Coolant Temperature Sensor.
The 2.5 liter 4 cylinder engine used in the 1998 Ford Ranger is NOT an interference engine , according to the Gates website ( so the answer is NO )
3.8litres
A 1998 Mercury Mystique with the 4-cylinder 2.0 DOHC appears to have a non-interference engine. Therefore, if the timing belt breaks, there should be no damage to the valves/pistons.
The main difference between a 1998 Saturn SL1 and SL2 lies in their engine configuration. The SL1 typically comes with a single overhead cam (SOHC) engine, while the SL2 is equipped with a dual overhead cam (DOHC) engine. This results in differences in power output and performance between the two models.
If the check engine light is blinking , an engine cylinder misfire has been detected