Fuel injector cleaner..

[4JGtootsie]

A good substitute for injector cleaners is changing fuel filters and flushing the tank and fuel lines once in a while.

I have seen a cummins injector cracking its cups because of blockage. Its also possible that a push rod or even a rocker arm bending or breaking in extreme cases.

Of course that is a cummins fuel system. Just always remember hydrolock (conrod bending) and that fluids are incompressable,

Also excessive water contamination in diesel especially common rail systems will cost you!