Lack of lubrication
"Jack Rabbitt" starts
High mileage
Doing "Burn Outs"
A bad rear differential causes vibration, noise, and fluid leaks. This can impact a car's acceleration and driveability, and cause very serious problems if not addressed.
The hub bearing can go bad and create noise.
Thermocycling.
There can be a few reasons for a catalytic converter to go bad. One of the causes could be clogs. Other reasons include plugs not working right, and bad exhaust valves.
Serious. If it is bad enough the vehicle will not move.
They get soggy in damp weather.
A bad transmission.
Broken gears. The differential or ring gear or pinion gears are broken.
Bad groung and or bad sending unit.
Low fluid and dirty fluids.
Bad electrical fixtures.
Old age. Wear. Abuse.