This post address vehicles that are not starting after having sat for a period of time. For information regarding a vehicle that died while driving and then failed to restart, please see this post.
First off, i recommend keeping a few things in the car for just this type of situation. A small socket set with metric or standard sockets (depending on the make of vehicle) a standard screwdriver, a Philips screw driver, a pair of pliers, a can of starting fluid or brake clean, a flashlight, jumper cables, and a tow rope. This small assortment of tools will get you far in life. Even the best mechanic is worthless with out some tools.
To start, try to crank (turn over) the engine. Observe what happens. If the car turns over very slowly, you most likely have a dead battery. Run your wipers, roll your windows up and down (if electric) and note the speed at which these work. If the wipers and window motors move slowly, your battery is most likely dead. Attempt to jump start the vehicle.
Take note to make sure you are connecting positive to positive, and ground (negative) to ground. Look at the battery for the denotation, often times battery cables have been switched and you can not necessarily trust red for positive, black for negative. Also, you may need to let the donor car run for a length of time while attached to the dead vehicle before the car will start. If the car dies as soon as the donor vehicle is detached, you most likely need a new alternator.
If you try to turn the motor over and nothing happens, or if you tried to jump start the vehicle and still nothing happens, you likely have a problem with your starter. If you have a bad starter, often you will be able to hear a faint “click” when you first try to start the car.
A starter generally looks like this,
It has two or three wires going to it, and generally has a sticker on it which reads “do not strike with hammer”. If you can find the starter, check to make sure the two or three wires are all attached and seem to be in good condition, which generally they will be. The small wire is the signal wire. Occasionally this small wire will have come off, or will have broken, however, more than likely, the starter is just going bad. They will hit a point where they are not making good contact somewhere inside them, and thus they don’t energies.
If you have something that will reach the starter, try taping it, preferably while someone tries to start the car. This process will often get a starter that is going out to turn the car over a few last times. This process of tapping the starter is why they generally have a sticker which reads “do not trike with hammer”. Although hitting the starter may get it to work a few last times, it’s also not good to go beating the thing to death. Use a bit of common sense and you’ll be fine.
If you happen to have a test light, you can check for power to the signal wire while someone turns the key. If you have no power at the signal wire during cranking, than hot wire it from the main lead to the starter, and the car will start.
The next set of options is for a car that is turning over normally. If the car turns over, but fails to start, you have a crank, no start condition. Common causes for a crank no start condition are loss of fuel, loss of spark, loss of compression or a flooded motor.
If a motor is flooded, it has too much fuel in the combustion chamber to start. All modern cars have a flood clear mode. If you hold the accelerator to the floor, the car will automatically go into flood clear mode. As long as you hold the accelerator to the floor, the car will not open the injectors, and will thus clear the engine of the excess gasoline. If the car is flooded, and you put the car into flood clear mode, the car will start to fire as soon as the engine is clear of the excess gasoline. Once the car begins to fire, simply let of the gas and continue cranking until the engine starts. Common causes of flooded motors are: old ignition parts, a very dirty throttle body, too little ignition timing, or an old and stretched timing belt.
A loss of fuel is a very common cause of cars not starting. The easiest way to check if the car has lost fuel is to spray a bit of starting fluid (brake clean also works) into the intake. Remove the air intake boot, open the throttle plate and spray a reasonable amount of fluid into the intake. Replace the intake boot and attempt to start the car. if the car fires and dies, or at least pops a bit, you most likely have lost fuel.
Try dumping a gallon or two of gas into the gas tank. Your fuel gauge may have stuck in the middle and left your car out of gas. Similarly, your fuel pump may have stopped working. Much in the same way that tapping a starter may get it to work, tapping a fuel pump can often jog it into working. Bounce the back of the car, kick the gas tank, bang the top of the access panel for the fuel pump (if equipped), anything to jostle the fuel pump may get it to work. Lastly, you may have lost injector pulse. If you have a test light, unplug one injector and check to see if the test light lights up during cranking.
Another common cause of a crank no start condition is loss of spark. Remove one spark plug, connect it to the ignition cable or coil pack, depending on the type of ignition system you have, and try to start the car. As long as the spark plug is grounded and you have a good ignition system, you should be able to see a spark arc across the spark plug. Loss of spark varies widely from car to car, but may be a bad distributor, bad crankshaft or camshaft sensor, a bad plug wire, bad cap or rotor, bad ecu or even a bad spark plug. If you have lost spark, you probably need to take the car to a shop.
The last cause of a crank no start condition we will cover is loss of compression. This event occurs when the timing belt or timing chain brakes, slips or strips. If you have a trained ear, you will hear that the car has lost compression as soon as you crank it over. The engine may turn over extremely quickly due to no resistance in the motor, or it may turn over with a strange off rhythm. Regardless of what has caused the loss of compression, you will most definitely need to take the car to a shop to repair a loss of compression.
One last thing to consider, if you use BG products to maintain your car, you receive a free road side assistance card. These cards are good for a gallon of gas, having someone unlock your car, or a free tow to the shop. This road side assistance card is one of the many reasons we recommend using BG products when maintaining your car.