Why Is My Car Clicking When Trying To Start?

Nobody wants to hear a clicking sound or just one click when trying to start the car, especially in a hurry.

There are many reasons why a car may produce a clicking sound when trying to start, from a bad battery to a bad starter or something even more serious. Fortunately, reasons are often relatively simple and can be solved rather quickly.

Published: December 28, 2022.

How Car Starting Works

Cars with internal combustion engines, both diesel and gasoline engines, have a very similar starting sequence - when the key in the ignition is turned, or the start button is pressed, a number of things happen to start the engine:

• The ignition switch sends a signal to the starter solenoid, which engages the starter motor (which is an electric motor, obviously), which sends full battery power to the starter motor via thick cables connected to the car's starting 12V battery.

Note: diesel engines also warm up the diesel fuel to make it more fluid, especially at lower temperatures.

• The pinion gear engages the flywheel, which is a heavy disc attached to the engine's crankshaft, allowing the starter motor to rotate the crankshaft and compress the fuel-air mixture in the cylinders (gasoline engines) or to compress the air (diesel engines).
• As the engine turns over, the spark plugs ignite the fuel-air mixture (gasoline engine), or the fuel is injected into cylinders (diesel engines), causing the engine to start.
• When the engine is started, the starter motor is disengaged, and the engine runs on its own power, recharging the battery and powering electric and electronic systems via the alternator and the charge/voltage controller.

This is, of course, a simplified description of starting process, but detailed enough to understand what is going on when trying to start the engine and the importance of individual components involved in starting the car engine.

Where Does Clicking Sound Come From?

The clicking sound usually comes from the pinion gear - the starting battery has enough power to engage the starter motor but not enough to spin the engine.

However, the car can produce different clicking sounds when trying to start.

Multiple Rapid Clicks

This is very common after cold nights - the battery has enough power to engage the starter motor but not enough to spin the engine.

Also, the battery has enough power to do it repeatably, causing the starter to start and stop rapidly, forcing the pinion gear teeth to hit the flywheel teeth - this can even cause mechanical damage to the gears, not often, but when clicking starts, don't force it ...

Single Click

The battery has just enough power to engage the starter motor once, after which it is almost dead. Also, dashboard lights may flicker, and the car's electronic system may report various other electric issues, not just discharged battery.

But, a single click may also be caused by a faulty starter motor, starter solenoid, locked up/seized engine, or something else that can be detected only by car diagnostics (at the workshop).

Note: when the battery is almost completely drained, or the contacts are dirty, the car can produce multiple, relatively slow clicks - the battery engages the starter, after which it needs some time to recover (usually less than a second).

How To Solve Car Starting Issues?

If the car clicks and it won't start, there are a few possible reasons, including:

• Dirty, loose, or damaged battery connectors: check the battery connectors and, if needed, clean them. Also, check the starter and starter solenoid connections, just in case. If You have a wet/flooded lead-acid battery, check the electrolyte level and if required, add some distilled water.

• Dead or discharged battery: if the battery shows less than 12.0 volts, it is discharged below 25% SoC (75% DoD) and simply doesn't have enough power left to crank the engine. If the battery voltage is below 11.6-11.8V, the battery is considered fully discharged.
• Faulty starter motor or starter solenoid: if the starter motor or starter solenoid is faulty, the car won't start. The only solution is to tow the car to the workshop.

Note: actually, one may also use some metal object and hit the starter and starter solenoid a few times - the catch is that both the starter and solenoid may have electrical issues (bad contacts) that can be solved with some tapping.

• Faulty electronics: if the car electronics are faulty, the battery and starter may be OK, but the car won't start - tow the car to the workshop.

Personally, if your car clicks, your best bet is that You have issues with the battery, which can be solved relatively quickly, at least temporarily. In the long run, take the car to the workshop and let the certified mechanics check it.

How To Start The Engine With Discharged Battery

If You are in a hurry and your battery is discharged, try jump-starting a car with jumper cables or a car jump starter.

Jumper Cables

Jumper cables can be used to start the car with a bad battery using a car with a good battery or simply using another fully charged battery.

If You are using another car battery, start the car, just in case.

First, connect the dead battery's positive terminal to the positive terminal of the good battery and then the negative terminal of the good battery to the negative terminal of the bad battery.

Let them be connected minute or two to build a surface charge on the bad battery.

Crank the engine and disconnect the cables in reverse order.

Car Jump Starter

Connect the car jump starter to the car battery (first positive/red cables, second negative/black cables).

Start the car jump starter and let it do its diagnostics.

When signaled by the jump starter, usually a greed LED light or similar, crank the engine and disconnect the cables in reverse order.

Of course, whatever You do, stay safe - if You are, for example, cleaning the battery terminals, use gloves and goggles, just in case.

Also, if You are unsure what to do, don't do anything - call for assistance and let them tow the car into the repair shop, simple as that.

Stay calm and stay safe...