Just clicks once when try to start

My truck don't start it clicks once I replaced starter and starter relay on the firewall don't know what to check next

My car has 170000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hi there:

Usually if the engine cranks over one time and the starter was recently replaced, it’s often caused by the starter input shaft not engaging the flywheel correctly. This is either caused by a misalignment issue or the battery has low cranking amps and needs to be replaced. However, there could be multiple issues causing this problem, so it might be a good idea to have a professional mobile mechanic complete a car is hard to start inspection first, so they can help diagnose the exact issue and you can make the appropriate repairs.

How to Identify and Fix Common car Problems ?

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You hear a single click

Usually, this points to a faulty relay or solenoid, or a bad or jammed starter motor. Solution: Rock your car back and forth or tap the starter motor with a hammer and try starting the engine again.

A single loud click could mean that there are troubles with the starter motor or the starter solenoid—which together act like a crank to help get your car`s engine going—or more specifically from a failing or bad starter relay that`s not sending enough electric current from the battery to the starter motor.
A single “click” sound comes from the engine compartment or from under the car. This could mean that the solenoid is trying to engage but that the internal components are stuck and unable to work properly. Repeated “clicking” sounds usually indicate a dead battery.
It might also be a bad solenoid, starter failure, or engine timing. But battery, battery cable, and alternator problems are the most common cause for this click or clicking noise. So, your next steps are to do a little investigating and testing to try to determine what the problem might be, so you can fix it.
The starter solenoid is an electromagnetic switch that engages the starter motor. How can I tell if my starter solenoid is bad? If you`re having trouble cranking the engine over but the battery is charged, or if your starter won`t disengage after starting the engine, it`s likely a starter solenoid issue.
If your starter relay has gone bad, the electrical signal will never make it from the battery to the starter motor. As a result, your engine won`t turn over – no matter how many times you turn the key. A faulty relay often produces an audible clicking sound when you turn your car.
Starter motors should make noise when you turn your ignition key fully to activate your car. If you turn the key and do not hear anything, there`s a chance that there`s something wrong with the vehicle`s ignition switch.
If rusting is the issue, you can bypass the bad starter solenoid wire. To do so, use a 12V wire to directly provide current from the car`s battery to the point where the starter and solenoid connect. You`ll hear a click sound indicating that the connection is made. Now turn on your ignition system.
Dead car battery: A dead battery is the most common reason why a car won`t start. If you have a battery tester, check your battery to see if it`s weak. If you don`t have one, try to jump start your car with jumper cables.
Let someone turn on the ignition key or press the starter button. Observe the light — if it doesn`t turn on, the solenoid is likely failing to transfer power and might need replacement. However, if the light turns on but there`s no clicking sound or starter engagement, the issue lies with the car starter.
One of the best ways to determine if a car fuse has blown is by using a test light. It should illuminate both ends of the fuse, and, if it doesn`t, it needs to be replaced. Sometimes, a blown fuse is caused by a damaged wire, motor, or other part.
If you feel and hear clicks, the relay works on one side – the side with the energizing circuit and coil. However, if there was no sound from the horn, the relay has a problem along the contact circuit.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

My 2003 ford explorer wont start up just get click click click click click click click click
ANSWER : If the battery is weak and the voltage is dropping to below 9 volts you will get the clicking without the starter turning the motor. Have the battery voltage checked and if battery cannot hold a load then replace it and clean the battery terminals and recheck system to see if it starts.

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.

Car won’t start. When trying to start, starter makes a clicking noise and then closed back hatch recloses.
ANSWER : It sounds like there is some type of drain on the battery. When there is low voltage in a battery, it can cause several symptoms. The electrical systems can act very strangely when they don’t have the correct voltage being supplied. When a battery won’t hold a charge, it can be caused by a wiring issue, a bad battery, or some type of parasitic draw that can slowly pull voltage from the battery. Some electrical diagnosis done by a professional, such as one from YourMechanic, will be necessary to pinpoint the cause.

Cranks over start than dies
ANSWER : Hi There,
The idle air control valve is a small valve on the engine’s intake system that reads the air intake as it comes into the motor. This is controlled by the car’s ECM which uses this information to make adjustments to the air/fuel ratio depending on various inputs such as outside air temperature, intake air temperature, load and various other things. As you accelerate, your car’s engine is receiving a much higher dose of fuel than when at idle and conversely, when you let off the gas pedal, there is a sudden change in this fuel supply as a result of your foot letting off the pedal. When this happens, the job of the idle air control valve is to bring this deceleration down to a slow and smooth idle rather than suddenly cutting off the fuel supply causing the motor to die. When the idle air control valve is not working properly, this cause a disruption in this process resulting in the engine not being able to idle properly. I would recommend having a professional come to your location to diagnose and inspect your vehicle.

I put a penny in place of a fuse, tried to start my car and now it wont start and makes a grinding sound when i try to start it
ANSWER : Hi there. Putting a penny in place of a fuse, not recommended, replace with the correct fuse. The fuse is there, to protect the circuit. If the fuse blows, there is a short to ground. The grinding sound, when you try to start your vehicle, could be the starter. The starter drive could be at fault or the flywheel has a problem. I recommend having your vehicle’s no start be diagnosed and repaired by a certified technician from YourMechanic.

Car was sometimes not starting, not even cranking when i turned the key then after a few times itd start. Now it ont start at all
ANSWER : Hi there:

Without being there to inspect your vehicle, or having information about what type of car, truck or SUV you own, it’s very hard for us to give you some advice. You might want to have a professional mobile mechanic complete a car is hard to start inspection; so they can come to your location and determine why your vehicle is having these issues.

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.

I have a 2007 Lexus ES 350. I tried to start the car and the lights came on, it clicked but would not turn over. I tried a coupl
ANSWER : Whether a jump start will start a car, or even power lights, depends on how good the connection is and whether or not other issues in the car’s electrical system (such as a faulty battery to body ground cable). Also, even if you have a good connection, if the starter motor is faulty (or there is a problem in the starter circuit), the car won’t start. Generally, jump starts should only be used as a last resort, or in an emergency, due to the risks and the potential for short circuits and vehicle damage. Making things worse, if you battery is dead (or defective) if you are successful in jump starting the car and you drive it, you then run the risk of overloading the alternator as the alternator tries to both re-charge a dead battery and run the car’s electrical system.

To prevent damage, and to aid in diagnostics if it turns out that you have problems in addition to a dead battery, the battery should FIRST be load tested. If the battery fails that test, or even if it "marginally" passes, the battery should be replaced outright. Once the battery is replaced, assuming the car then starts, the charging system should be fully checked out and that is standard YourMechanic protocol once a battery is replaced in a vehicle. Test the charging system ensures that a faulty charging system was not the cause of the battery dying in the first place. If a battery is replaced, due to it failing a load test, and yet the car still will not start, a no start diagnostic would then be performed. If you want all these steps performed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a no start diagnostic and the responding certified mechanic will start with the battery issue (testing the battery is already included in the no start diagnostic and, as noted, is the first step) and get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.