It is everyone’s nightmare: First thing in the morning, cup of coffee done, breakfast done, get in the car, turn the key and nothing. A bad way to start the day. There are reasons why a car won’t respond to your energetic twists of the ignition switch. It might even be a problem that is inexpensive to fix.
The most obvious thing to check is your battery. Even if you managed to unlock the doors with your remote and see the “idiot lights” illuminating, it is not a sure thing that the battery is okay. It might just have enough juice to do just those things. Do not go out and buy a new one yet. Check first if you have left a vanity light or even the headlights on overnight. If this is the case, have the battery recharged and you will have solved the problem. If you have jumper cables, a jump start from your friendly neighbour will have you up and running in no time. Make sure you drive the long way to work so the battery has enough charge for the drive home.
If the battery checks out okay and the car still won’t start, you could have dirty battery terminals. Check that both cables are not encrusted with corrosion. Pour hot boiling water over them if they are. Make sure to remove the cables and clean the terminals and battery posts with sandpaper before putting them back. This will ensure maximum contact and allow the car to start.
If after all that, all you hear is still just a click, you may have a bad starter. If you have an older car, a sharp rap on the starter with a spanner may get you a short reprieve to get you to the workshop. Failing that, a push start is another way out. In any case, a new starter is the only cure.
Sometimes, the engine will crank over healthily but won’t start up. This may be a small problem with a quick solution, or it may be a big one. Engines need fuel, sparks and air to start. So this is where we start the search.
Fuel supply is the easiest thing to check. First and foremost, did you forget to fill up the car? You may laugh, but this is the most common problem when cars won’t start even though they are cranking over. Assuming you have a full tank, the next port of call is the fuel pump. On some cars, it is possible to hear the pump priming as you turn on the ignition. If you cannot hear it, try listening as close as possible to the fuel tank as someone turns the ignition switch. If you cannot hear it, try underneath the bonnet (some cars have the pump located there). Assuming you cannot hear the pump at all, check the electrical box to locate the fuel pump relay. Locate the correct relay (a workshop manual is useful here) and it should click when you turn the ignition switch. Switch relays over if it does not click (make sure they are the same type). Sometimes the relay is protected by a fuse, so you should check that as well.
The pump runs but the car won’t start?
The battery and starter have checked out and now it is down to the rest of the electrical system. First thing to check is the fusebox. Make sure all fuses are intact and also without corrosion (newer cars are sensitive to even the slightest corrosion). Clean any suspect fuses or replace them with new ones.
Check relays as well because the electronic computer also runs on a relay. Some relays click as you switch on the ignition and some will click as you crank the engine over. If it all checks out, turn your attention to the spark plugs. Remove one plug and reinstall it on its cap. Rest it on the engine block and crank the engine over. There should be sparks coming from the plug to the engine block. If there are none, the coil may be bad. This is difficult to test without a multimeter and only a qualified mechanic will be able to test it properly. Older cars are easier as they have a distributor cap, distributor arm and coil that are easily tested and replaced if faulty. Newer cars will need a mechanic to run a diagnostics test.
There are other issues that may prevent your car from starting.
Loose starter: Loose starter bolts will cause it to wiggle, which causes it to turn the engine over. This is easily seen and heard.
Starter lockouts: Automatic cars have electrical lockouts, usually in the “Park” position. Check that the gearlever is fully in the Park position before attempting to start the car again. A cable may also be loose and not allow the lockout to be disengaged.
Bad injectors: A bad injector can throw the entire fuel system off and keep the engine from firing, especially when the engine is warm.
Faulty cold start valve: A failed cold start valve will keep your car from starting when the engine is cold. Sometimes it may even cause the fault to appear when the engine is warm.
Chipped flywheel or ring gear: Your starter’s gear connects with the gear teeth on your flywheel or ring gear. This is easy to hear and may make the starter lock up.
Bad engine control unit (ECU) or mass (air) flow sensor (MAF): If your engine’s ECU or any part of the system’s electronics fail, your car won’t start. Unfortunately, you will need to leave this type of diagnostic work to a qualified repair shop.
Normally, going through the first few paragraph of this article will solve your problem. If you have gone further than that, you may need to find your friendly neighbourhood foreman.