Audio clips to help identify common car faults
These audio clips may help you identify some of the most common faults that can cause problems with your car.
Unless you know what you are doing, delving under the bonnet to check for or correct faults can be unwise and even dangerous. We recommend that you seek appropriate professional assistance to confirm and deal with any problem.
Regular servicing according to the manufacturer's guidelines along with frequent maintenance checks will help avoid problems developing.
Partially discharged battery audio clip
File size: 592Kb
Download time: 1min 26sec at 56Kb/s
Engine cranks slowly on the starter and gradually slows to a stop.
Partially discharged battery; not enough power left to start the engine.
Other simple symptoms to look for:
Watch the dashboard lights while cranking. If they dim, but don't go out completely when the key is turned, it confirms a partially discharged battery.
The most common causes are lights accidentally left on or an interior light left on, which is often due to a faulty door switch.
Go through all the switches and controls and make sure everything is turned off, wait 15 minutes and try again. A battery in good condition may recover enough to start the engine. Driving the car for an hour or so in daylight may recharge the battery.
If the problem persists then seek professional advice.
Completely flat battery audio clip
File size: 161Kb
Download time: 1min 23sec at 56Kb/s
No engine cranking when you turn the key, but an irregular metallic clicking noise from under the bonnet.
Completely flat battery.
Other simple symptoms to look for: Watch the dashboard lights. If they go out completely when the key is turned it confirms a completely flat battery.
If the car has been left for several days or weeks, it could be caused by a simple current drain – even the alarm will drain a partly worn battery after a couple of weeks.
If the battery is completely flat after the car has been left overnight, it is almost certainly worn out and needs replacing.
Check your manufacturer's handbook and seek professional advice.
(Petrol engines only)
Immobiliser audio clip
File size: 955Kb
Download time: 2min 19sec at 56Kb/s
Engine cranks at normal speed, but doesn't start.
For petrol engines, the most common causes are flooding (too much petrol entering the cylinders) or no spark at the spark plugs.
Watch the dashboard lights. A flashing key symbol indicates an immobiliser problem – check the manufacturer's handbook for the correct starting procedure. A strong smell of petrol from under the bonnet is a sign that flooding is the likely cause.
A cold engine needs extra petrol to start, but too much petrol will mean there is not enough air for it to ignite. A car due for a service may suffer from this problem. In damp weather, moisture on the spark plug leads can stop the ignition system working. A car which has been started when cold, then turned off within a minute or so will often suffer from flooding the next time you try to start it.
Again, check the manufacturer's handbook or seek professional advice.
Faulty starter audio clip
File size: 336Kb
Download time: 49secs at 56Kb/s
A loud metallic 'clunk' when you turn the key to the start position, but the engine does not turn over.
The starter motor (the loud 'clunk' is the starter solenoid operating).
The dashboard lights remain bright when the key is turned. (If they dim significantly, or go out, the problem is a flat battery – see above)
Poor connection of the heavy duty leads or worn or sticking brushes in the electric starter motor.
This requires professional assistance – check the manufacturer's handbook and seek professional advice.
Slipping alternator drive belt audio clip
File size: 792Kb
Download time: 1min 55sec at 56Kb/s
A loud screeching noise, usually just after the engine has started. You may also hear it when manoeuvring slowly or after driving through a deep puddle.
Slipping drive belt (often called the fan belt).
If the headlights are on you may notice them dim slightly at the same time as you hear the screeching noise.
The alternator drive belt (often called the fan belt) is not tight enough because it is worn or stretched or incorrectly adjusted. This makes it slip on the pulleys. It happens when there is a heavy load on the belt, such as when the alternator is trying to recharge the battery after starting the engine, or when the power steering pump is working hard as you turn the steering wheel with the car moving slowly. This fault is more common on diesel vehicles since the heavy duty batteries place a greater load on the alternator.
Check the manufacturer's handbook for its recommendations and seek professional help.
Fuel problem audio clip
File size: 827Kb
Download time: 2mins at 56Kb/s
Check your most recent fuel receipt in case the wrong fuel has been added. If you have put the wrong fuel into your car, don't turn on the ignition or start the engine.
The engine fires for a second or so, but then dies. After a couple of attempts at starting, then engine won't fire at all.
No fuel getting to the engine.
No smell of petrol from the engine.
Safety switch tripped, low fuel level, incorrect fuel type
Many modern cars have a safety switch (sometimes called an 'inertia switch'), which turns the fuel pump off if the car is involved in an accident. Check the manufacturer's handbook for the location and how to reset it or seek professional advice.
Fuel injection systems often need a minimum amount of fuel in the tank to start the engine, so if the fuel level is low, there may not be enough to start the car, even though it drove to the location. Try adding at least 5 litres of the right fuel.
Fuel must be purchased in a properly designed, labelled and sealed container.
Always refill the fuel tank with the correct fuel for the vehicle before it gets very low.
Timing belt audio clip
File size: 498Kb
Download time: 1min 12sec at 56Kb/s
The engine turns over much more freely than usual and the noise 'dips' less frequently than normal.
Broken camshaft drive belt (also known as the 'timing belt'). This belt turns the camshaft to operate the engine's valves. When it breaks, the pistons continue to move, but the valves do not, usually resulting in contact between at least one piston and valve. The belt most commonly breaks while you are driving and instant internal engine damage is very likely – by the time you register the loss of power, the damage has been done. Subsequent turning of the engine by a mechanic will not cause further damage.
None. This is a fault that requires immediate professional help. Check the manufacturer's handbook for advice and seek professional assistance.
(10 November 2011)