Some Examples: Air filter clogged Exhaust leak plugged cat clogged fuel injector malfunctioning fuel pressure regulator clogged fuel filter malfunctioning fuel pump spark plugs, wires, cap, rotor,
coil Vacuum leak dirty throttle body malfunctioning fast idle thermo valve (similar to vacuum leak) low oil (unless there is an oil level sensor) belts gaskets seals rings low compression bearing damage (rod knock)
Broken cam rocker fell / broke off broken valve spring stuck valve critical engine damage (windowed the block) wiring, fuses, relays starting system - ignition switch, starter, relay Cooling system - clogs, leaks, flow (may throw a code if you overheat) transmission clutch (es) driveshaft, differential, axles brakes suspension tires hvac lights
Broken cam rocker fell /
broke off
broken valve spring stuck valve critical engine damage (windowed the block) wiring, fuses, relays starting system - ignition switch, starter, relay Cooling system - clogs, leaks, flow (may throw a code if you overheat) transmission clutch (es) driveshaft, differential, axles brakes suspension tires hvac lights
broken valve spring stuck valve critical engine damage (windowed the block) wiring, fuses, relays starting system -
ignition switch, starter, relay Cooling system - clogs, leaks, flow (may throw a code if you overheat) transmission clutch (es) driveshaft, differential, axles brakes suspension tires hvac lights gauges
In the 5 years that I owned it, these are the things that
broke or degraded prematurely: PCV tubing
Ignition coils Ignition coil wiring harness (degraded insulation) Timing belt (replaced at 50,000) Clogged oil pick - up tube Radiator fan