What causes a car to suddenly fail to start?

1. The battery is dead.

Sometimes when we wake up in the morning and find that the car does not start normally, it is likely that our trunk is not completely closed, and the trunk light is always on, causing the battery to run out.

2. The spark plug cannot be ignited.

The spark plug itself is easily damaged, the high-voltage line is short-circuited, etc., resulting in the spark plug can not be ignited, and the other is that the spark plug of poor quality is also the reason for the failure to start normally.

3. The starting circuit is faulty.

There is only a slight "click" sound when starting, and there is no response, which is caused by the starting relay card issuance. At this time, as long as you press the tail of the solenoid to force the solenoid to move forward, the starting circuit can be turned on, so that the engine can start.

To identify the cause of the fault, the battery should be tested first for the diagnosis of such faults when the engine does not start. It is necessary to find out if the engine does not start because the battery is insufficient.

Detect the boot system. Detect the circuitry in the engine starting system first. From the perspective of the most basic composition, the circuit of the starting system generally includes the following basic parts, that is, the battery, the starting motor and the cable connecting these parts.

Of course, in addition to this, ignition switches, starter relays or solenoid coils, as well as in-vehicle anti-theft systems, are also important components of the starting system.

See if there's a problem with the battery.

There are several reasons why the car won't start: one. No oil. Two. Power. Three. No air intake.

Let's analyze these four items approximately:

One. No oil.

The reasons for the failure are:1The oil pump relay is working poorly. 2.The oil pump is not working well. 3.Out of gas.

Fault Detection: 1Detection of oil pump relays:

Turn on the key switch and don't hit the motor, you will hear a click, which means that the relay is working properly! If there is a continuous clicking sound, check whether the tie wire is loose. If the relay is judged to be damaged, the light relay can be interchanged with the oil pump relay.

Drive to the repair shop and buy a new relay.

2.Detection of oil pump: Generally, it is checked with an oil pressure gauge, because it is self-excluded.

There is no oil pressure gauge! The easiest way to do this is to remove the tubing and turn on the key switch on the position. Do not start the motor.

If the oil pipe is injected, it means that the oil pump is normal. On the contrary, it is not normal.

Two. Power. Cause of failure:

1.The head of the battery pile is loose. 2.

The high-voltage ignition coil is damaged. 3.The cylinder line is damaged.

4.Whether the starting relay is plugged in properly or not, it is damaged. 5.

Whether the insurance is burned out. 6.Whether the motor is working properly.

7.Whether the main output cable of the computer case is loose.

Fault Detection: 1Detection of loose battery pile head: observe whether the instrument is displayed, if the whole car has no electricity, open the hood, and observe whether the battery pile head connection is loose and oxidized. Loosen it with a wrench, and pour boiling water on the pile head for oxidation.

2.Detection of ignition coil: You can use a multimeter to check the resistance value of its primary and secondary coils, which should be within the conforming range, and the secondary resistance should be larger than the primary resistance!

But that's not sure if it's in good condition! Unplug the cylinder wire, observe it for flashover, and see if there is any leakage in the insulation! The jumping fire should be blue, and the sparks are thick and long!

3.Detection of steel wire: check the resistance value with a multimeter, which should be within the load range. Unplug the cylinder cord and observe it for a flashover. Or skip the fire and replace.

4.Detection of starting relay: There is a problem with the general relay, and there is no response when hitting the motor. Plug and unplug the relay again to see if it starts normally! Replace the relay or motor shorted.

5.Detection of the fuse: Open the fuse and observe whether the fuse indicator is normal and whether the fuse is burned. Replace the fuse.

6.Motor detection: mainly listen to whether the sound of the motor is normal. If the carbon brush of the motor is severely worn, it can be temporarily activated by hitting the motor with a hammer. Go back to the repair shop for replacement.

7.Whether the main output line of the computer box is loose: check whether the plug-in of the computer box and its wiring and each sensor is loose. Fastening is recommended.

Three, no air intake.

Cause of failure: Damage to the eccentric wheel and wear of the eccentric shaft, resulting in the intake and exhaust valves cannot be opened and closed.

Troubleshooting: Call a tow truck!

Hello, the common reasons why a car suddenly won't start are:

The battery is dead or the voltage is insufficient;

starter failure; starter relay failure; The starter fuse burns out;

Fuel pump failure; Fuel pump fuel supply relay failure Poor contact; The fuel pump fuse burns out;

Ignition switch failure (ST gear cannot be turned on);

P n gear signal switch failure, P n gear poor contact (automatic gear);

crankshaft camshaft position sensor;

Ignition coil failure ignition coil ignition no signal; Wait.

The car suddenly won't start, let's see what happened, have you had the same experience?

Hello, this situation may be the reason why the battery is not electric, you can find a 4S shop or an insurance company to help rescue.

There are several reasons why the car suddenly fails to start:

The battery is dead or the voltage is insufficient;

starter failure; starter relay failure; The starter fuse burns out;

Fuel pump failure; Fuel pump fuel supply relay failure Poor contact; The fuel pump fuse burns out;

Ignition switch failure (ST gear cannot be turned on);

Intake pressure sensor, crankshaft camshaft position sensor;

P n gear signal switch failure, P n gear poor contact (automatic gear);

Injector failure; (Uncommon).

Ignition coil failure ignition coil ignition no signal;

Failure of the air flow meter;

Locked circuit oil circuit by immobilizer system;

There is no fuel in the fuel tank; (Pure human negligence).

ECU failure; (Uncommon).

Failure of the concealed lock switch;

The oil supply system circuit has an open circuit or a short circuit.

The engine water temperature is too high; (in case of protection system).

What's going on when the car doesn't start? Is it because of the engine?

What is going on with a car that was working well yesterday and suddenly it won't start? There may be many reasons why the car is running well and suddenly cannot start, such as engine failure or spark plug aging, but the mechanic said that the probability of the car not starting due to engine failure is relatively small, and the car cannot start is likely to be a problem with this part.

This part is the battery of the car, many people know that the reason why the car can start, mainly by the battery to provide electrical energy to ignite, if the battery has a problem, no matter how to fire it will not help.

Some car owners may not understand that "the battery will be automatically charged when the car is running, why is there no power"? Although the car does charge the car when driving, it is still very common for the battery to run out of power (professionally called battery loss), which is generally caused by the following reasons:

1. After parking and turning off the engine, use the on-board electrical equipment in the car for a long time.

Now there are more and more functions on the car, and there are many more humanized comfort configurations, such as seat massage function, car refrigerator, car TV, ** and other entertainment systems, these car electrical equipment will consume a lot of electrical energy when in use, if you stop and turn off the engine, continue to use these devices in the car for a long time, it is likely to consume all the power in the battery, resulting in the car can not start.

Second, the battery naturally ages, reaching the limit of use.

No matter how good the battery has a fixed service life, the battery will naturally age after many times of flushing and discharging, the service life of the general battery is 2 years, if the better battery is used properly, the longest can be used to about 4 years.

When the battery reaches the limit of use, the ability to charge and discharge is getting weaker and weaker, generally manifested as "not easy to ignite" or when the engine is not started, the lights are obviously dim, then it is necessary to replace the new battery, if the new battery is not replaced in time, it is likely that at a certain time, the battery is completely "turned off", and the car cannot be started at this time.

3. The car is parked for a long time.

However, some car owners encounter such a situation, that is, their car is a new car less than 1 year after they were bought, the car is still very new, after the car is parked and turned off, they have not used electrical equipment in the car for a long time, how can it not catch fire? The reason is actually very simple, it is likely that the car has been parked for a long time and has not moved.

What many car owners don't know is that the battery will automatically discharge when the car is not in use, until all the power is consumed, so if you don't need to use the car for a certain period of time, don't stand for a long time, try to start 2 turns, or idle in place for a few minutes, so that there will be no time to start the car next time.

Summary: If your car suddenly can't start, then don't rush to send the car for repair, first check whether the battery is losing power, if it is only the battery loss, it is much easier to deal with.

Answer: It is possible that the fuse responsible for starting the motor has burned out. Automobile fuse is a kind of current fuse, commonly known as "fuse", when the circuit current exceeds 2 times the rated current of the fuse, it will blow in a few seconds, playing the role of circuit protection.

Burnout phenomenon:

1.It is the bottle that has electricity but the vehicle cannot be started, but it must be noted that when the vehicle cannot be started, remember not to fire continuously, which will cause the battery to continue to discharge and lead to the embarrassing situation of complete power.

2.While driving, the vehicle tachometer shows normal, but the speedometer shows zero, and the ABS warning light lights up at the same time, which indicates that the fuse corresponding to the ABS is burned out. Some informal businesses will unplug the fuse of the management ABS when transporting vehicles, in order not to increase the mileage, but this brings great hidden dangers.

1. The battery loses power, or the connecting wire is broken or the joint is loose; 2. The contact of the starting relay is seriously ablated or its coil is broken; 3. The contact of the starter electromagnetic switch is seriously ablated or its suction coil is broken; 4. The internal winding of the starter DC motor is broken or short-circuited; 5. The armature shaft of the starter is bent, and the gap between the shaft and the bearing is too tight; 6. The commutator is seriously ablated, the brush is worn too much, the brush is stuck in the brush holder or the brush spring is too soft.

There is a fault in the electrical circuit, oil circuit, or trip computer, etc.

Reasons why the car won't start What to do if the car won't start.

1. Automobile battery. The battery is the basic power of the car to start**. The battery is mainly responsible for running the starter motor.

If the battery is insufficient, it will not be able to run the starter motor, and if the starter motor cannot drive the flywheel to turn the engine, it will naturally not be able to start. When activated, there will be no sound, or a clicking sound. Noticeably feeling inadequate.

In this case, the first consideration is the cause of the battery.

2. Car starting motor. The starter motor is responsible for driving the engine. As soon as the ignition switch is ignited, there is a power supply to the starting motor, and the starting motor will run.

Drive the engine and let the engine run. If there is a power supply at this time, it is necessary to ensure that the battery has sufficient power. The starter motor is not running.

At this time, it is necessary to consider whether the carbon brush of the starter motor is worn out, or the magnetic suction of the starter motor is burned out.

3. Automobile ignition system and fuel supply system. Excluding the first and second reasons, it is necessary to consider whether the ignition is faulty or the fuel supply is not available. In general, the probability of an ignition system appearing is rare.

However, it is not excluded that it is generally a line failure or an ignition relay that burns out and causes it to fail to ignite. The sound when starting is the same as the usual start-up sound, but if it can't be started, then check if there is no fuel supply. If there is no oil, it will generally be the relay of the fuel pump that has been burned, or the fuse has been burned.

If there is electricity to the fuel pump. If the oil pipe is out of oil, then you have to consider whether the fuel pump motor is damaged and the oil supply is not supplied, which affects the normal start.

1. Take the wire: This is a necessary item for the car to take the electricity, do not take two wires to make do, because the instantaneous current of the vehicle at the start can reach 200-600A, and the diesel car even reaches 1000A, if it is calculated, 10 square copper wires can ensure the smooth and safe start, so the car battery connection line must buy the right brand, the quality is the best, do not try to be cheap. This is one of the must-have items in the car, once the battery is out of power, you can take it out and use it, and you can also help others when you don't use it.

2. Emergency power supply: This is a new type of power bank like a thing, there are two kinds of lead-acid and polymer lithium battery, which can help the vehicle with a loss of power to start, and can also have lighting, charging mobile phones and multi-functional supplies used with an inflatable pump to inflate the car. And it is generally portable, very lightweight, if you have it, you don't have to ask others for help.

Be sure to charge it in time after use and keep it full of power to deal with emergencies.

3. Positive, first connect the positive: first turn off all the electrical equipment on the car, make the key in the OFF position, open the cabin cover to find the battery, there are positive and negative poles written on the battery, generally the red "+" sign is the positive pole, and there are generally two wires, at this time, take out the red one, open the battery cover, pinch the clamp on the head to clamp firmly the positive pole of the battery of the electric car, and the clamp at the other end to clamp the positive pole of the battery of the rescue vehicle. Be sure to connect the positive electrode first, then the negative electrode, do not reverse the order, and do not use the battery clamp to touch anywhere except the battery pile head.

4. Negative connection, negative connection: After the red positive electrode is connected, take out another wire, first clamp the negative pole of the tram battery, the negative electrode is generally black "—" number, and then pinch the other end of the clip, from beginning to end the clip do not touch other places, to clamp the negative pole of the rescue vehicle battery, when the connection will pop out of the electric spark, please don't be afraid, this also shows that you are right. The reason why the negative electrode is not connected first is because the whole vehicle is basically a negative electrode (that is, commonly known as "tie iron"), if the negative electrode is connected first, when connecting the positive electrode, the clip will cause a short circuit and burn the parts on the car when it touches any conductive place in the body.

5. After starting the vehicle, first remove the negative, and then dismantle the positive: after the battery is connected, the rescue vehicle will first ignite and charge the battery, and then the no tram enters the vehicle to open the key, at this time the instrument light will be lit smoothly, and then try to ignite (not more than 5 seconds), if it fails to start smoothly, step on the accelerator of the rescue vehicle, and the speed is kept at about 2500 rpm, and then the tram is ignited again, if the starter is no problem, the car has oil in the case of general can be started smoothly, after the non-electric vehicle starts, Remove the negative clamp first, then remove the positive clamp, for the same reason as why the negative pole is followed by the fourth one.

The positive and negative poles of the battery must not be reversed, and the order of assembly and disassembly should be strictly in accordance with the order of first connecting the positive and then the negative, and the first dismantling and then the positive.