A car that won’t start usually indicates a problem with the battery, the starter motor, the spark plugs or the fuel filter. You can often identify the cause yourself by paying attention to what the car does do: do the lights come on, do you hear a clicking sound, or does nothing happen at all? Below, we’ll walk you through the most common causes step by step and explain how you can fix the problem yourself.
How do you determine the cause?
The quickest way to find the cause is to pay attention to the signals the car gives when you turn the key. If the dashboard lights do not come on and it is completely silent, the battery is probably flat or the connections are loose. If the lights do come on but you hear a repeated clicking sound, the battery does not have enough power to drive the starter motor. If you can hear the starter motor turning but the engine does not start, the problem is likely to be with the spark plugs or the fuel supply. By following this sequence, you’ll avoid replacing the wrong part.
Flat or worn-out battery
If the lights come on but you only hear a click or nothing at all when you turn the key, the starter motor is probably the cause. The starter motor is an electric motor that sets the pistons in the engine in motion, after which the internal combustion engine takes over. The starter motor’s gears can wear out over time, preventing the engine from turning over properly. You can replace the starter motor yourself by first disconnecting the negative terminal of the battery, then the positive terminal, and finally unscrewing the two mounting bolts on the starter motor. Always read your car’s manual, as disconnecting the battery in modern cars sometimes requires a special procedure.
Worn spark plugs or glow plugs
If the engine won’t start even though the starter motor is turning, the spark plugs may be the cause. In a petrol car, spark plugs produce a spark that ignites the fuel in the cylinder, whilst a diesel car has glow plugs that act as heating elements to bring the diesel fuel up to the correct temperature. You can recognise worn spark plugs by soot build-up, deposits or a damaged insulator; they are located in the engine’s cylinder head. Glow plugs generally need replacing after 80,000 kilometres. Always replace spark plugs once the engine has cooled down completely; use a spark plug wrench and never pull on the spark plug lead to prevent damage.
Clogged fuel filter
If you have ruled out the battery, starter motor and spark plugs and the car still won’t start, a blocked fuel filter may be the cause. The fuel filter traps dirt and impurities before the fuel reaches the engine, but becomes clogged over time. A blocked filter restricts the fuel supply, meaning the engine does not receive enough fuel to start. You can replace the filter yourself by disconnecting the fuel line, removing the old filter and fitting a new one. The car may not start straight away after replacement, as the system needs to be bled first.
The effect of the weather on starting problems
Cold weather is a common cause of starting problems, as the battery delivers less power whilst the engine actually needs more power to start. You should therefore check the battery twice a year, preferably before and after winter, and keep the terminals clean and free from corrosion. In freezing weather, you can briefly switch on the headlights before starting the engine, to give the battery a slight warming boost. If the car is left stationary for a long time during the winter, use a trickle charger to keep the battery charged. These precautions will prevent you from being caught out on a cold morning.
Need spare parts? Japoto is here to help
At Japoto, you’ll find batteries, starter motors, spark plugs and fuel filters for Japanese and Korean brands, with over 70,000 items in stock. Not sure what the problem is or which part you need? Please get in touch via 0596 – 57 2992 or send an email to info@japoto.nl.