How to fix a car that won't start

Whether at home, at work, at school or on a shopping trip, it's never nice to sit in the driver's seat and find your car won't start. It can seem like an overwhelming experience when you are not only trying to start the car, but also trying to determine the cause.

Luckily, there are usually three common areas to explore if you want to find out in advance why your car won't start. The first area to look at includes checking the battery and connections to the starter. Second is the fuel and the fuel pump, and third, and usually the most common culprit, is spark problems in the engine.

Part 1 of 3: Battery and Starter

Necessary materials

• Digital multimeter
• Donor car
• Connecting cables

The most common reasons for a car not starting are usually related to the car's battery and/or its starter. By starting our investigation here, we can quickly find a solution to why the car won't start.

To examine a dead battery, we want to start by turning the key to the "on" position. Go ahead and turn on the headlights of the car. Notice if they are strong and bright, if they are weak and dim, or if they are completely off. If they are dim or do not light up, the car battery may be dead. A dead battery can be brought back to life with jumper cables and another vehicle by following these steps.

Step 1: Park both cars close. Park the donor car next to the car with the dead battery. You need both engine bays next to each other so that the jumper cables can reach each battery end to end.

Step 2: Securely Attach Clamps to Terminals. With both cars turned off, open each hood and locate the battery for each car.

• Have a friend hold one end of the connecting cable. Make sure the two clips are not touching each other.

• Connect the red clip to the positive battery terminal, then the black clip to the negative terminal.

Step 3: Now do the same for the donor car.. Once the jumper cables are connected, start the donor vehicle and make sure that all accessories such as the heater/air conditioner, stereo and various lights are turned off.

• These additions place a strain on the charging system, often making it difficult for a malfunctioning vehicle to start.

Step 4: Allow charging of a dead battery. Let the donor car run for a few more minutes. This is what allows a dead battery to charge.

• After a few minutes, turn the key in the receiving car to the "on" position (do not start yet). Make sure all accessories are also turned off.

Step 5: Start the receiving vehicle. Finally, start the receiving vehicle and let it run. While it is running, have someone help you remove the jumper cables from each vehicle. Remember to remove the negative clamp first and then the positive one.

Step 6: Drive the car for 15 minutes.. Drive a car with a freshly charged battery for 15 minutes. This should allow the alternator to fully charge the battery.

Step 7. Check the battery. It is recommended that the battery be tested shortly after this surge to determine if it needs to be replaced.

• FunctionsA: A certified mechanic will be able to test your battery if you don't have a battery tester. If the car has a good battery, but the engine does not turn, the starter may be to blame, and it needs to be replaced.

The starter can be tested with a digital multimeter attached to the signal wire between the starter and the battery. Have a friend turn the key and try to start the car. When trying to start, this wire should indicate the battery voltage it is receiving. If your power probe or multimeter does show battery voltage, you can be sure that the wiring to the starter is good. If the starter just clicks or makes no sound, then the starter is to blame.

Part 2 of 3: Fuel and fuel pump

Step 1: Check the fuel in the car. Turn the key to the "on" position and watch the gas gauge. In most cases, this will show you how much fuel is left in the tank.

• AttentionA: Sometimes the gas sensor can fail and show you have more gas than you actually have. If you suspect a low fuel level is the problem, take a gas bottle and pour a gallon of gasoline into the car to see if it starts. If the car still starts, then you have found out why the car does not start: the gasoline sensor was inaccurate, it needs to be repaired.

Step 2: Check the fuel pump. Remove the gas tank cap and listen for the sound of the fuel pump turning on when the key is turned to the on position.

• This step may require the help of a friend to turn the key while you listen.

Sometimes it can be difficult to hear the fuel pump, so using a fuel gauge can show if the fuel pump is working and also tell us if it is supplying enough fuel to the engine. Most modern cars have an access port for connecting a fuel gauge.

Watch the fuel pressure gauge while starting the car. If the pressure is zero, the fuel pump wiring needs to be checked to make sure power is being supplied to the fuel pump. If there is pressure, compare your reading to the manufacturer's specification to see if it is within acceptable limits.

Part 3 of 3: Spark

Step 1: Check the spark plug. If you have enough fuel, you need to check for spark. Open the hood and locate the spark plug wires.

• Disconnect one spark plug wire and use the spark plug head and ratchet to remove one spark plug. Inspect the spark plug for signs of failure.

• If the white porcelain is cracked or the spark plug gap is too large, the spark plugs must be replaced.

Step 2. Check with a new spark plug.. To make sure the car is getting spark, take a new spark plug and insert it into the spark plug wire.

• Touch the end of the spark plug to any bare metal surface to ground the spark plug. This will complete the chain.

Step 3: start the engine. Have a friend crank the engine over while you hold the spark plug to ground.

• A warning: Do not touch the spark plug with your hand, otherwise you may get an electric shock. Be sure to hold onto the rubber end of the spark plug wire to avoid electric shock. If there is no spark in the car, the ignition coil or distributor may be at fault and need to be checked.

While the three most common areas have been provided, there are actually quite a few reasons that can prevent a vehicle from starting. Further diagnostics will be required to determine which component is preventing the car from starting and what repairs are needed to get your car back on the road.