Intermittent no start and electrical problems?

/i went to start the yesterday evening and the car would not start there was no dash board lights however the radio worked and the headlights came on even thou they were turnt off and there not automatic i checked all the fuses and they were fine. i rechecked it this morning and nothing still but about a hour ago i went out to show my friend what the car was doing and it started there car is a vauxhall astra 2005

My car has 109125 miles.
My car has a manual transmission.

Experienced mechanics share their insights in answering this question :
Hello. From what you describe, it would appear that your vehicle is experiencing some sort of electrical issue. If the issue comes and goes intermittently, then the first thing I would look at is the vehicle’s ignition switch. It may be possible that the switch has shorted or failed and is causing your issues. It may also be possible that there is some sort of electrical fault elsewhere, perhaps in the form of damaged or frayed wiring. I would start by checking the ignition switch, and then move on to the electrical system. If you need to have this looked at, a certified technician from YourMechanic can come to your car’s location to diagnose the starting issue and electrical problems in order to have this addressed.

How to Identify and Fix Common car Problems ?

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

When it comes to the vehicle not starting, and not having electrical power, always start by checking the battery. In your situation you can go remove the battery from the vehicle, and take it to have it tested. If it is bad, simply replace it and drive the care home.
Possible causes of a power failure could be either bad battery connections, a bad ignition switch, or a bad alternator. What you need to do is check your vehicle`s power sources.
If the car won`t start at all and the dashboard lights are flickering, it`s likely that the battery does not have enough charge to crank over the vehicle. In this scenario, you`ll likely need to replace the failed battery.
A damaged terminal with a loose fuse may cause electrical problems such as sudden, intermittent power loss to certain accessories or lights.
Bad Sensors

One common culprit for this problem is the crankshaft position sensor, which measures the position and speed of the crankshaft. The computer uses the information from this sensor to know when to fire the spark plugs. If the sensor isn`t working, the spark plugs won`t fire, keeping the engine from starting.

The most common car electrical system problems are problems with your car battery, an alternator that isn`t working properly, loose or failed spark plugs, a fatigued solenoid or starter, bad battery cables, electrical fuses that are blown, loose wires, or problems with your ignition switch.
Dashboard lights can become non-functional for various reasons. In case, the dimmer switch on the dashboard is turned down or off, the dashboard lights will not show. Also, a blown fuse or a bad lightbulb can cause the non-functionality of these dashboard lights.
The alternator is supposed to provide the electricity for your car`s lights. If there`s not enough power to run your lights because your alternator isn`t working properly, they may run too dim, flicker, or not run at all.
The answer, though it may surprise many, is a resounding YES.
Occasionally, a fuse may blow for no real reason. In this case, simply replacing it is the only thing you need to do. But if you have a few fuses that blow out repeatedly, you likely have a deeper problem with your vehicle electrical systems. An overheated and melted fuse disrupts electricity flow.
your car fails to start: the engine`s computer uses the map sensor to gauge atmospheric pressure before the engine is started. a false reading could cause too much or too little fuel to be delivered to the engine. both conditions could keep it from firing up.
A Bad Crankshaft Position Sensor

The crankshaft position sensor monitors the position and rotational speeds of the crankshaft. Without the crank sensor, the engine control module (ECM) wouldn`t know when to fire the fuel injectors and ignite the spark plugs.

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.
Blown fuse – Sometimes the simplest explanation is the best one. A blown fuse in the starter circuit could be the cause of a no-start problem. Broken or corroded wiring – Damaged or dirty wires to the battery or to the starter solenoid (or wires that are loose) can prevent sufficient power from reaching the starter.
One of the first symptoms of a problem with the ignition module are engine performance issues. If the ignition module fails or has any problems it can lead to performance issues with the vehicle, such as misfires, hesitation, loss of power, and even reduced fuel economy.
A dead battery is one of the most common reasons why your car won`t start. Check the battery terminals for corrosion and clean them using a wire brush or battery cleaning solution. If the battery is old or damaged, it may need to be replaced entirely.
A blown fuse can cause a complete or partial failure of instrument cluster functions. Remember that an open fuse can indicate an underlying electrical problem. There could be a short circuit in the wiring or inside the cluster.
One of the most common problems you`re likely to experience with an alternator is a failure in the bearings. There are needle bearings in the alternator that allow the rotor to freely spin inside the housing, and those bearings can break down over time as a result of exposure to heat and dirt.
An illuminated battery light could be due to a number of issues, including: A loose or corroded battery cable. A problem with the alternator or voltage regulator. Damaged cells or plates inside the battery.
If all the gauges in a car suddenly stop working, it`s typically due to a broken fuse or faulty wiring. To start troubleshooting, you`ll need to locate the fuse associated with the instrument cluster. Once you`ve identified the fuse, you can inspect it to determine if it has blown or needs to be replaced.
Improper modification is one of the most commonly seen problems. The most common of these is tapping more than one conductor from a single connection point.
If the wiring is worn out to the point of exposure, then the wire may touch the metal frame or external surface. This will lead to a short circuit as well. Even if the wire moves around a lot and only comes into surface contact occasionally, these intermittent short circuits will eventually lead to a blown fuse.
A blown fuse signals a short circuit. This occurs when an electrical component draws a stronger current than it is designed to handle due to the device malfunctioning.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

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.

My 2001 c320 has an intermittent starting problem. I turn the key to start the car and nothing. There is no engine turn over. All
ANSWER : A YourMechanic no start diagnostic on the problem you have written in about involves first determining whether or not full battery voltage is reaching the starter motor itself. If not, then the circuit has to be traced from the battery onward, through the wiring, fuses, relay, ignition switch and so forth until the break in the circuit is found. On the other hand, if it is determined that full battery voltage (i.e., no voltage drop due to high resistance in circuit) is reaching the starter motor, that means you need a new starter. In the latter case, by the way, sometimes starter motors develop a "bad spot" on the armature and thus if you use a rubber mallet and strike the motor (the motor, not the solenoid housing), you can sometimes get the starter to work as the armature "jumps" past the bad spot. If the rubber mallet trick does work, of course, that is a further indication that the "intermittent" fault is within the starter itself. Do not use metal tools around the starter, by the way, as you can cause a short circuit to ground if you touch the exposed hot terminals causing damage and personal injury. If you would like a certified mobile mechanic to professionally diagnose and repair your no start problem, by all means please follow up with YourMechanic.

Car will not start intermittently while in PARK but always starts on NEUTRAL.
ANSWER : Hi there, thank you for writing in and providing a detailed description. I’d be happy to give my insight on what to do next.

I would make the same conclusion about the neutral safety switch. I think Pep Boys made the right call. I admit, I don’t like to call a part bad without being able to duplicate the problem, but anytime a customer states their car starts in neutral but not park, we replace the neutral safety switch. I can’t recall a time that this move was wrong.

The intermittent nature of your problem does’t change this diagnosis either. The same electrical connection can work one moment and not the next. Electricity works at the atomic level that we as humans can’t directly observe, which is why we have tools to do electrical testing. Your tow truck driver got it correct.

Hope this helps and best of luck! If you’d like help replacing your neutral safety switch, consider having one of our expert automotive technicians come to your home or office to do it for you.

Intermittent problem with car not starting and not cranking
ANSWER : Hello. This is caused by a loss of voltage someplace in the electrical system. Most of the time this is caused by a bad connection at the battery or a bad battery cable. I usually check and clean these connections and see if there is anything that is loose, or if there is any corrosion. If these are fine, then it may be a failure in the fuse box.

Either way, some electrical diagnosis will need to be done. If this is something that you are going to have fixed, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose the car starting problem and let you know what should be done.

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.

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.

New battery & fuel pump. Hours later car starts and shuts down 3X in a row. Finally it starts, 48 hours later, won’t start at all
ANSWER : Checking all the fuses was a good move. I would also want to put a scan tool on it and check for diagnostic trouble codes (DTCs) as well as seeing the data that the computer is seeing.

A fuel pressure test would be a good idea to verify correct pressure and so that you’d be able to eliminate that possibility. It should be 58psi on your Magnum.

I also recommend getting your battery tested (I know, it’s new, have it tested anyway) and be sure it’s charged to at least 75%. And yes, loose battery cable connections can result in electrical problems.

If you need some assistance with this, consider enlisting a certified mechanic who can perform the checks I’ve mentioned and diagnose your starting issue firsthand. The mechanic can then perform the necessary repairs once the problem has been isolated. Good luck.

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.