If you have difficulty starting your car, it can be hard to know what's causing this problem. Issues with such a broad array of causes can be frustrating - this article guides you through some of the facts behind the starting system, and the components that may be to blame.
Part 1 of 3: Getting to know the starting system
The starting system is fairly basic once you break it down. Knowing what is involved will help significantly when diagnosing your issue. Here are the components in the order they operate when you insert the key.
Step 1: Insert your key. The driver inserts the key into the ignition, which is mostly a security device so your vehicle can not be started by anyone. That key completes a circuit when turned which sends power to the starter.
Step 2: Starter pushes the flywheel or flexplate. The amount of power supplied from the ignition switch is not enough to turn over the engine. A solenoid on the starter will take that amount of power given and use it as a switch for a more powerful current.
The starter will drive a small gear known as the Bendix into the flywheel or flexplate pinion and rotate the ring gear.
Step 3: The engine turns over. At the moment the flexplate or flywheel is cranked over, the gas and fuel mixture is being pumped into the combustion chamber at the piston the timing is set trigger.
This is when the spark should be delivered from igniting that fuel and air mix. Once all of these factors have occurred in a timely manner, the engine should start and continue to run until the computer is told to shut it off.
At this point, the entire starting system has performed its function. The Bendix will retract and the starter will not engage until the next turn of a key.
Part 2 of 3: Most common issues with a hard start condition
Now that you know what parts are in consideration, you will have a better idea when determining what part is not performing its function.
Step 1: Start the car in Park. Make sure that before you start to test, that you attempt to start the car in Park. It may sound obvious, but it can be overlooked easily. Try switching the car to Neutral and attempting to start it again. If the vehicle starts in Neutral and not in Park, a neutral safety switch could be at fault.
If the key will not turn in the ignition, the steering wheel may locked. Rotate the steering wheel back and forth and listen for a click. Try turning the wheel again.
Step 2: Check the battery. A dead or partially charged battery will not supply the power that the starter needs to crank over the engine.
Begin by jump starting the vehicle. A simple dead or discharged battery will recharge from the alternator after running for a few minutes.
If the battery is bad and needs replacement, you are likely to experience this problem again, or even while driving. Your battery can be tested at home with a multimeter, or at your local automotive shop.
The battery may also have corroded or loose battery cables. If this is the case, clean the terminals and cables. The cables under the conduit also become corroded and need to be cleaned down inside of it.
Removal of conduit may be needed, but do this with caution and replace the cables if they are needing more than an inch cleaned. Verify the cables are tight and secure on the terminals.
- Note: If the battery needs replacement, and you are still able to drive your car after jump starting it, you may be running mostly off of your alternator. This causes a huge amount of extra stress on the system and will cause damage to your alternator.
Symptoms of a bad battery include a slow crank, or even a “clicking” noise when the starter is engaged with the key.
Step 3: Check the starter. Starters can last the life of your vehicle, but that is rare. It is likely at some point you will need to replace your starter.
The solenoid attached to the top of the starter can fail, as well as the the components inside. These can be bench tested at home or at your local automotive parts store. However, it is very rare that these tests include a “load test.”
This additional test not only tests the function of the Bendix to engage the engine, but also its ability to push the weight of the flexplate or flywheel. It is not uncommon for a failing starter to pass a bench test. You will hear a clicking of the Bendix engaging, or a slow turning of the engine if this is the case. You will need to replace the starter.
Step 4: Check the spark. Without spark to ignite the fuel mix in the combustion chamber, the engine will not start. It will turn over or “crank over” but will never actually run.
There are several ways to test for spark at home, but it can be a dangerous procedure if done incorrectly. For safest testing, use a spark plug tester, this will show you if the right amount of power is being sent to the plugs.
Spark issues are not limited to the plugs. Check the spark plug wires, the distributor or module, and plug gap. These all have a huge effect on the function of the ignition system.
Step 5: Check the fuel. If the wrong amount of fuel is being injected into the combustion chamber, or being injected at the wrong time, the engine will not start. Again, this will be a case where the engine cranks over, but will not actually run.
This could be caused by a few different parts including the fuel pump, fuel filter, fuel injectors, and fuel lines. Some of those options are a stretch, but do have an effect on the system. Start with the fuel injectors, and make sure they are clean.
Some of the other tests needed to inspect the fuel system are harder to do from home without the right equipment. You may want to proceed to other factors as a process of elimination if you suspect the fuel system is at fault.
Step 6: Check the compression and timing. Compression and timing are two more crucial components in the starting process.
Without proper compression the combustion in the chamber will not occur as needed. When these pressures are low, the engine will likely turn over rapidly as if there is not resistance. Timing will have a similar but opposite effect.
If the timing is off, it will likely slow down the ignition causing a no start or slow start.
Part 3 of 3: When does the malfunction occur
The exact moment in the process of starting in which you find yourself stuck, will tell you a tremendous amount about what part is not functioning. Look at the next few steps for more diagnostic help.
Step 1: Starter does not engage. If you turn your key, and hear only silence, your starter is not engaging at all. Check the power supply.
Inspect the battery cables and charge on the battery. This may be solved with a simple jump start, a new battery, or a new starter.
Step 2: Engine will not crank. If you turn the key and hear a “click,” the power supply is the first place to look. This is a sign that the power is not strong enough, or the starter is not strong enough. Either way, the click you hear is the Bendix engaging the engine without being able to turn it.
Step 3: Engine cranks but will not start. Like earlier parts of the list, this is one of the symptoms that can be caused by nearly all the components we have discussed. A discharged battery, a faulty starter, fuel, spark, compression, and timing can all negatively impact the starting of your vehicle.
Attempt to clean the battery terminals and secure the connection to the cables. Tap the starter in case debris is stuck, slowing the Bendix while spinning.
Try to tap the fuel filter while starting the vehicle in case the filter is to blame. This may free fuel to be sent to the engine (you can also knock debris into your lines and injectors which will cause major issues). Tap the starter while attempting to start the car. If the starting seems to improve, this will indicate the starter is faulty.
When your engine is hard to start, and you have places to be, there is not much time or patience for a lengthy diagnostic process. Replacing the starter is the most common repair for these symptoms. It can be done easily at home, or by a technician in less than a day. For help at your home or office, contact a certified technician, such as one from YourMechanic, to diagnose your hard start for you.
This article originally appeared on YourMechanic.com as How to Troubleshoot a Car That is Hard to Start and was authored by Jessica Howe.