97’ engine problems

I have a 97’ XK8 with about 90k miles. 3 owners (my grandma and me are the last 2 most recent owners).

The engine will start/turn over and run from anywhere from 30 seconds to 2 min. Whole left side of motor not running. We have spark at the coils. The battery is brand new. Car has history of running and shutting off while driving (with my grandma). She gifted the car to me and now i can’t get it to run.

Could it be the timing chains? Until 02 the tensioners were plastic and prone to breaking.