Yes
Rocker arms dont break. Pushrods bend and lifters malfunction, but rocker arms rarely if ever go bad. A bad lifter will make an obnoxious taptaptap noise. A bent lifter will cause significant backfiring through the carb or fuel induction system.
2 rocker arms per cylinder(engine). If it is an exotic supercar, it can 1 per axle to operate the inboard shocks/springs.
Valve clearences (ohv), bad valves, timing out, bad rocker arms, piston slap. Easy tests for all of the above, just google them. Some cars just have an annoying tick, only way to fix them is a good radio or cd player
bad transmission
yes
The rack and pinion effects the steering of the vehicle directly. It is definitely not recommended to drive a car with a bad rack and pinion because of this.
It is bad to drive it with anything crucial to the car damaged. so yes.
NO
Yes it does.
Toyota
get ready to have a not so well running car. its best to keep everything assigned to its cylinder