My car won’t start, neither does my auto. Start. Sometime it might start if I jump it sometimes it won’t.

IMy car won't start, neither does my auto. Start. Sometime it might start if I jump it sometimes it won't. it sometimes does it and my check engine light will appear and then it does it again days later and it will disappear

My car has 90000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hi there. There are a number of issues that will make a car hard to start. Everything from the electrical system to the fuel system to the actual starter itself can be the problem. Finding the root cause of a hard starting engine can take some investigation. Ignoring a hard starting issue can further damage the vehicle, which will often result in a more expensive repair. You might want to have a mobile mechanic complete a car is hard to start inspection so they can pinpoint the source of the issues you’re having and recommend the right repairs be completed.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

The root of the problem is likely a dead battery. The rapid clicking noise you`re hearing is likely the last of the battery`s charge. Notice if your car lights are dim when you try to turn the ignition—dim lights will be another indicator that the problem is in the battery.
The most common reasons a Chevrolet Impala won`t start are a dead battery, an alternator problem, or failed starter.
Why won`t my car start but I have power? If you attempt to start up your car but the engine won`t turn over and the dashboard lights up, then you most likely have an issue with your battery. You could have a damaged or corroded battery terminal, which is stopping the engine from starting up when you fully turn the key.
Connected to the battery is the alternator, which works to generate power for your vehicle`s electrical components. When you have a brand-new battery but still can`t start the car, the alternator might be the issue. Cold and damp climates may increase wear on an alternator, causing it to fail.
Usually a rapid clicking noise is a good indication that your starter motor isn`t getting enough electrical current to engage – basically your solenoid is trying to engage but can`t make the connection.
If your vehicle won`t start, it`s usually caused by a dying or dead battery, loose or corroded connection cables, a bad alternator or an issue with the starter. It can be hard to determine if you`re dealing with a battery or an alternator problem.
It might be a battery or alternator problem.

If the source of the clicking is electrical, the starter (a small motor energized by the battery that gets the engine running) doesn`t have enough juice to stay powered. So instead, it rapidly turns on and off and produces a clicking noise!

Common Signs of a Bad Starter

The engine won`t turn over. The most common signal that your starter has a problem is if nothing happens when you turn the key or push to start. Unusual noises, such as clinking, grinding and whirring. If you ignore these sounds, it can eventually lead to damage to the engine flywheel.

Low oil pressure might be the cause of those ticking sounds. When vital engine components don`t get adequate lubrication, it might cause other problems, and the engine starts to make these noises. A broken valve train component, such as lifters or cam followers, can also cause ticking, tapping, or clicking sounds.
What if your car won`t jump-start? First, try running the other engine for five more minutes before trying again to start yours. If your car still doesn`t start, you may need a new battery — or it could be a sign of a more serious problem.
Whirring sound: This might mean that the solenoid is worn out and unable to engage the flywheel. The sound you hear is the armature in the starter spining on its own but unable to crank the engine to start.
Bad Sensors

Sensors that fail to send information to the computer may cause the engine to run less efficiently, and they can sometimes be the cause of an engine that won`t start. One common culprit for this problem is the crankshaft position sensor, which measures the position and speed of the crankshaft.

If nothing happens when you turn the ignition key to the “Start” position, it means that the starter motor doesn`t turn over the engine. Most commonly this could be caused by a low battery; read above How to check the battery.
An effective method to determine whether it`s your battery or alternator that`s gone bad is to connect jumper cables from a running vehicle`s battery to yours. After a few moments, try starting your vehicle. Once it`s started, remove the jumper cables — if your engine stalls, your alternator has probably gone bad.
In most cases when you hear a repeating clicking sound as you brake, it is likely coming from one of three sources. First, it could be a wheel bearing that is wearing out. Second, it might be a warped brake rotor or a sign that brake pads are wearing out and need to be replaced.
Misaligned Valves

But lack of maintenance and other issues can cause misalignment, which makes it difficult for the valves to open and shut, resulting in an engine clicking sound. Alternatively, faulty CV joints can also cause engine ticks under the valve cover.

Jump starting a car can damage your battery too, as the alternator is pumping in current at a higher rate than the battery can handle. This causes the battery to heat up, bending the battery plates, leading to the shedding of active material (lead dioxide) and causing a build up of debris in the bottom of the battery.
If you`ve replaced your battery but the engine still won`t start, it could actually be an engine problem. A seized engine won`t turn over, and that often resembles a bad starter or dead battery. If you suspect that your problem stems from an engine issue, it could take hours to diagnose and repair.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

My car won’t start, neither does my auto. Start. Sometime it might start if I jump it sometimes it won’t.
ANSWER : Hi there. There are a number of issues that will make a car hard to start. Everything from the electrical system to the fuel system to the actual starter itself can be the problem. Finding the root cause of a hard starting engine can take some investigation. Ignoring a hard starting issue can further damage the vehicle, which will often result in a more expensive repair. You might want to have a mobile mechanic complete a car is hard to start inspection so they can pinpoint the source of the issues you’re having and recommend the right repairs be completed.

My car will not start Intermittently. I purchased a new battery 2 weeks ago and yesterday the car wouldn’t start. Got a jump and
ANSWER : The issue you are having is probably due to an intermittent fault in the starter motor itself or a deficiency in the starter electrical circuit, for example a large voltage drop due to a poor ground or a high resistance connection. These issues can be readily diagnosed and resolved on a mobile basis if you request a hard starting diagnostic. If you request that diagnostic, the responding certified mechanic will get this resolved for you promptly. Based on Toyota’s Factory Service Manual, the battery should not be disconnected if the vehicle engine is running. The battery acts as a large resistive voltage sink and consequently taking the battery out of the circuit, while the alternator is still running, can create a voltage spike on the car’s electrical system which is not good for voltage sensitive components such as the engine computer. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Car won’t start. The check engine light, battery light, and oil change light are coming on. I tried jumping the car and nothing happened. Why won’t my car start?
ANSWER : Hi and thanks for contacting Your Mechanic. If sometimes your vehicle will start with the new alternator and sometimes it won’t, then there is a loose connection in your charging system. Check all of the wires to the alternator and to the battery. Make sure that the battery cables are clean and tight. Make sure that the wires to the starter are clean and tight. A loose ground to the ignition system will cause the vehicle to not crank over. Check all of the ground wires from the battery to the starter. Make sure that they are clean and tight. If you need further assistance troubleshooting your no start situation, then seek out a technician, such as one from Your Mechanic, that can assist you.

Map sensor car won’t start up good ?
ANSWER : Your MAP sensor is an important input for your computer. It helps determine the load on the engine to calculate the correct amount of fuel to inject. It sometimes takes a few seconds for the vehicle to realize that the sensor is not producing a good signal.

At that point, it will use other methods to determine the fuel rate, such as pre-programmed fuel maps, throttle position, etc. I would suggest replacing the MAP sensor and retesting. If you would like to have it checked first, a certified technician from YourMechanic will be able to scan your vehicle and test components to determine the root cause of your starting issue before making a repair.

Vehicle won’t start, once it’s jump started it only stays running until you turn it off, then it work start again without jumping.
ANSWER : Hi there. There could be two problems here. It is possible that your battery is bad and will not take a charge from your alternator while driving. In that case every time you shut your car off you will not have enough juice to start it again. Inspect your battery – it should have at least 12.5 to 13 volts to start your car, if it doesn’t you will need to replace the battery. The second problem could be that your alternator is bad and not charging your battery, in this case you will need to replace your alternator. Both the battery and the alternator can be tested in your car. If you would like to have the car checked for you, a certified professional from YourMechanic can come to your car’s location to diagnose the starting problem and proceed with repairs.

The car crank but won’t start
ANSWER : Hi there. This does sound like an issue with the wiring. If the check engine light is coming on every now and then this means that when it does not come on there is no power to the computer. This can be the wiring harness issue or an ignition switch problem. I would have to test for voltage to the computer when the problem is occurring to be able to find where the issue lies. If you need assistance, a certified YourMechanic technician can be dispatched to your location to inspect your vehicle’s non-start issue and suggest any necessary repairs.

Sometimes car won’t start, sometimes car starts great – 1998 Mercury Grand Marquis
ANSWER : I usually try not to split hairs when it comes to batteries. If it is 3 years old or older, and it gives you trouble, it’s most likely time to replace the battery. Load tests are okay, but do not cover all that can go wrong internally.

Did you fully charge the battery first? Does the car sit for extended periods? You may consider having a local expert check the battery with an advanced tester that will check for most problems. They can also check your alternator. A bad battery can ruin an alternator so is it really worth it? If you would like to have this checked, a local technician should diagnose your battery in person to see if it is ready to be swapped.

Fuel pump engages. Batery good, alternator good volts, jump start helps when wont start. Temp does not matter. Intermittent?
ANSWER : Hello. Thank you for writing in. There are several reasons your vehicle may only start when jump starting. The first and most common is a build up of resistance that is causing you to need a boost of voltage to get the engine started. This may be due to poor battery cables, a bad ground connection, a poor starter solenoid, and a couple of other issues. The first thing you want to do is perform a visual inspection of the starting system. Make sure there is no corrosion build up in the battery cables. You can also check the resistance across these wires and make sure you have a solid connection between components. You then want to make sure the starter solenoid is doing its job. It is responsible for taking the small amount of electricity sent by the ignition and turning it into a huge electrical charge that is strong enough to push over the engine with the help of some gear ratios in its favor. Do some more testing, and stick to the basics before assuming its something seriously complicated.