A bad internal knocking sound; excessive smoke out of the exhaust pipe when running; overheating; no power on exceleration; these are a few of the first indications.
It needs replacing every 60,000 miles.
Fuel pressure regulator
You know the heater hose on a vehicle needs replacing when it beings to swell and soften. The heater hose runs from the intake manifold to the heater core.
IF YOU DONT KNOW, YOU PROBABLY WONT BE REPLACING AN ENGINE.
(1) Spark plugs need replacing. (2) Spark plug wires need replacing. (3) Distributor cap needs replacing. (4) Injectors are dirty and need cleaning or replacing (5) Fuel filter needs replacing. (6) Fuel pump needs to be checked.
Basically it means that the bulb needs replacing.
Your converter is clogged and needs replacing.
A failed catalytic converter is one of hundreds of parts that can cause the check engine light to be on.
If its leaking or has been bent or crushed it needs replacing.
Read your drivers manual, the information you are looking for will be in there.
generally if an engine overheats, but then does not overheat when heater is turned on, is a good indication that the engine thermostat is stuck and needs replacing
You won't know it needs replacing - it fails catastrophically, without any symptoms. Factory recommended replacement mileage is 95,000 miles. If you have passed that mileage you are living on borrowed time.